MUI macros not working anymore in my script

[Yathosho]

i've been away from nsis from months, in fact i haven't even touched my old windows machine lately. however, i found myself in the position that i needed to update an old script of mine, but all of a sudden it produces errors that didn't happen before.

code:
!insertmacro: MUI_PAGE_LICENSE

Error in macro MUI_INTERFACE on macroline 54

Error in macro MUI_PAGE_INIT on macroline 3

Error in macro MUI_PAGE_LICENSE on macroline 5

it took me a while to figure out, that for unknown reasons, the nsis projected which is sitting in a dropbox folder, suffered from synchronization problems. my custom ui, basically a modified MUI_nodesc, was 0kb in size. i changed the ui in the script to MUI_nodesc, but the problem persists. any ideas what could be the problem, all other resources by my script are intact. nothing was changed on the license page or the license itself since i last compiled my project successfully.

edit: interestingly, the standard MUI compiles the script