That bites. I’m moving your post to Beyond the Manual so you can get community input on settings. MoaG is for finished projects.
First - yes, always remove the plastic masking!
When it’s burning you generally would want to speed it up and not slow it down, so I’m not sure on your logic.
Generally acrylic is acrylic (*edit, this isn’t acrylic, but MDF so use PG draftboard settings to start), so the first thing I’d do is try, with the plastic masking removed, to run it through using the PG settings. If not, then speed it up by some number and try again. The goal is to get it to cut through with the lightest touch possible.
Here is a test template you can work with: