Code fails to save, even if it's unchanged.

[GavinFF-SS]

Describe the bug

So basically, I'm working on code for a Sugary Spire P-Rank Build mod I work on, and I'm editing the code for Fireass. In UTMT normal, it doesn't even load and I can't edit it, but when using UTMTCE, I can edit it but it fails to save.

Reproducing steps

Edit code for gml_GlobalScript_scr_player_fireass try to click off you can't, you get error.

Setup Details

1. Undertale Mod Tool: Latest Bleeding Edge, but it still happens on UTMTCE, the version where I can actually edit it.
2. GM 2023.6
3. Sugary Spire P-Rank Build With Candied Chasedown Playtester Build installed. (cannot link to this for reasons like it's a leaked build, and I was trusted to not leak the CC playtester build)

[Jacky720]

This is likely linked to #1084 if the reason it can't compile is use of structs.