CypherWolf:
While the good advice from Vit3D works, it is not necessary to go deleting keys or complex maneuvers. The keys are useful and on the contrary, you can add more keys, to place the character in suitable poses, which will help you when polishing the skin rigging.
Regarding the distortion you experience when "converting to SKIN", let me explain: It is not the SkinWrap modifier who is dependent on frame position. It is the skin modifier itself, which stores a reference frame in to the modifier data.
So here it is what you need to do:
The RL templates come with a "standard" pose at frame ZERO but also bring a T-pose at Frame 500. Move the time slider to 500 and you will have the avatar standing in Tpose.
Apply the SkinWrap modifer to your new mesh and give it the proper skin parts as you already did. Convert it to skin. The new mesh might be distorted. Don't worry!
Now check this image below:

YOu see to the right there is a section Advanced Parameters. Thre is a check box "Always deform" and just below an input window labeled "Ref Frame".
What you actually need to do, without messing with the keyframes, is:
-Once you have "converted to skin", and the mesh gets all distorted, TURN OFF the skin modifier (click on the little light bulb next to it). When you do that the mesh gets back to normal, no distortion!
-Now UNCHECK the Always Deform CHECK BOX. Then change the "Refrence frame" to the frame you are, probably 500 if you are working using a T-Pose-
-Now Click on the SKIN On switch (the light bulb, to make it white again)
-You will see the mesh does not distort! Now just enable the "Always Deform" Check box!
No need to delete keyframes! Remember: The Skin modifier STORES the keyframe where it was created. What you learned is how to reset that keyframe to a new one!
Hope this helps!

Mike Aparicio-Reallusion Certified Innovative Content Developer