Now that's a weird project file for sure (you can open .rpp files with a text editor btw., they're 'human readable', kind of an XML format.).
It contains identical 'MARKER' lines several thousand times.
That's (mainly?) why it's so big.
Any idea how that could've happened, using a script that deals with markers / regions by chance?
I've deleted (only) all MARKER lines in the project file which reduces size to ~ 1MB.
https://www.dropbox.com/s/fgah31va7v...ipped.RPP?dl=1