Sometimes we have to work with what we can work with -- back in the day, when our PCs weren't powerful enough for true NLE, we used workarounds that might serve you well with your underpowered setup.

What I think I'd do, if I were you, is not render to my final output size.  Clearly your editor can't handle that, and it's no good if you can't get it setup the way you want.  So render to, say, 320x240 PNG (or as large as your PC *can* handle).  The nice thing about this is your video editor shouldn't care when you finally DO render to the final output -- it will update the sequence automagically the next time it loads.  But in the meantime you can work with all the layers, get them working the way you want, and THEN re-render to your final size (overriding exactly the same files, with the same names), load up your editor for JUST the output, and output it.

It's called working with proxies, although in this case it's not *strictly* the case (I'm not sure what you'd call it, exactly) and what we used to do all the time, back in the day.  Should be plenty workable enough for you without jumping through hoops.

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

@Mike .... Interesting .... all the references I've been making to 'proxy' files were those that are created in the NLE 'automatically' when selected. What you're suggesting is a 'manual' proxy approach...

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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time!   - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

Most NLEs rely on converting "image sequence" files into proxies by creating highly compressed MP4 or even WMV - neither of which support an alpha.  There are a few AVI and QT codecs that allow an alpha, but in my experience they tend to be optimized for the "Pro" market so they are either uncompressed or use less compression - and therefore they are more about convenience than performance.

Mark >>>>> ....Most NLEs rely on converting "image sequence" files into proxies by creating highly compressed MP4 or even WMV - neither of which support an alpha.<<<<
that's good to know ..... so I won't go down that rabbit hole then .... thnx

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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time!   - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

OK - So from where I stand (at the moment at least), numbers 1, 2 and (possibly) 4 are OUT. Then with 5 and 6 - because they rely on keying with 'color' I have certain reservations about the cleaness of the key.
That leaves me with number 3, which, given what Mike has 'suggested', AND what Mark has 'warned about', then a 'manual' proxy creation would involve a similar amount of work/steps to #3.
Yeah --- I'd say #3 but with 'manual' proxy creation in place of a 'lossless' format creation ......  need to do some tests ....


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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time!   - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

No, I was suggesting doing #1, but just do it with a much lower-res PNG.  Your machine ought to be able to handle that, and when you are finished with your edit just go ahead and re-render at the higher res you want, reload the editor (with the project) and then output it (you can even output it at the lower res just to make sure first).

If your machine can't handle that lower res there's something wrong, somewhere (even my old laptop could do that, and it's REALLY old, like 7 or 8 years, which in computer terms is a dinosaur).

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Alienware Aurora R16, Win 11, i9-149000KF, 3.20GHz CPU, 64GB RAM, RTX 4090 (24GB), Samsung 870 Pro 8TB, Gen3 MVNe M-2 SSD, 4TBx2, 39" Alienware Widescreen Monitor
Mike "ex-genius" Kelley

After much deliberation as well as testing I've come to the following conclusions:
● Regarding 'proxy' generation in Vegas Movie Studio 15 ●
(assuming a low performing system and/or large 4K video files).
This software has a confusing 'dual' approach to proxy creation - well it fooled me, (not helped by '0 results returned' when searching 'proxy' in the manual).
But here's how it works...
☆ The 'manual' mode. By right clicking a file in the preview bin you can select 'Create Video Proxy' from the drop down menu. A short time later you'll be automatically editing with the proxies - seamlessly 'beneath the surface'. When you finally do your render, the original files will be automatically 'referenced' by the software for a full spec output file.
☆ The 'auto' mode. However, if you choose to bring in UHD video, a proxy file WILL BE created by default during import - and you won't really know you're using it. It's in this situation you can end up scratching your head because if you go to create your proxy (thinking you need to do it), your drop down list now has this feature 'grayed out'. Makes sense IF you know why. You can however disable this 'Auto Create Proxy for HD' under 'Preferences>Video'.

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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time!   - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

Sonic, that's an interesting approach. I'm currently working on a project where I renamed a folder containing an image sequence to something more logical, so Vegas Pro couldn't find it. Then, as with Movie Studio, Vegas prompts you and let you specify a new location. 

Another option, which may or may not be available in Movie Studio, is to do a Replace within the editor. In the Project Media panel right-click the image sequence and select Replace, which will then allow you select the hi-res alternative.

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@animagic ....
>>> Sonic, that's an interesting approach. I'm currently working on a project where I renamed a folder containing an image sequence to something more logical, so Vegas Pro couldn't find it. Then, as with Movie Studio, Vegas prompts you and let you specify a new location. <<<
Yes, about that 'message' ... "The following file could not be found in the specified location" (in Vegas MS there's 4 options):
● Search for the missing file
● Specify a new location or replacement file
● Ignore missing file and leave it offline
● Ignore all missing files and leave them offline
With option ●2 - I'm confused as to whether it's referring to two possible fixes: #A "Specify a new location"  #B "Specify a replacement file"
If that's what it means then only #B works for me (specify file).
I was hoping that the #A would mean simply 'pointing to a folder' and it would take care of the rest (finding the right files inside). - But it doesn't seem to work for me.

>>>Another option, which may or may not be available in Movie Studio, is to do a Replace within the editor. In the Project Media panel right-click the image sequence and select Replace, which will then allow you select the hi-res alternative. <<<
Brilliant! .... I wasn't aware of that one! Yes that could come in very handy! .... thanks animagic! 

I just watched a video about daVinci Resolve - it's an absolutely incredible piece of software ....

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Please be patient with me ..... I don't always 'get it' the first time 'round - not even the 2nd time!   - yikes! ... 

● MSI GT72VR Laptop, i7 7700HQ 4-Core 3.8 GHz 16GB RAM; Nvidia 1070, 8GB Vram ● iClone-7.93 ● 3DXChange Pipeline 7.81 ● CC-3 Pipeline 3.44 ● Live Face ● HeadShot ● Brekel Pro-Body ● Popcorn FX ● iRAY ● Kinect V2 ● DaVinci Resolve17 ● Mixcraft 8.1

"Specify a new location or replacement file" opens a file browser and gives you indeed the two possibilities you mention, with #B the one that is suitable for your purposes: specify a replacement file.

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