Moreover, this must be fixed in 1.1 patch for D2DP and that actually not present in PL version, too. GR and RotE never have this problem, both EN and PL. Where GOG take this UI...

I dont think that ticket to support change anything... So just forget it.

If you have enough enthusiasm you can try manually translate localisation dbf files, string by string from PL dbf's. Its too much strings... Hmm... It not from translated files, so must be help also this "easy way":

Copy T_.dbf files (T for "text"), Sinfo.dbf (in same folder), MFT and DLG files from Interf folder (sceneditor is optional), readme-manual-text files from root folder, and some of the .bik, wav and mp3 files in Briefing\Music (use VLC player to find what files with voice dubbing, also dbf can e opened as Tables files by Ms Office or LibreOffice). Copy some of the Exports folder map files (Tutorial and some optional others).
Install english version. Replace whole files "as is". Tutorial must be EN and PL version is a addition - required by Main menu "Tutorial" string. If some problems present in PL files itself they keep in that variant, but UI must be correct this time.

P.S. Do not copy whole Interf folder. As i remember this is from .ff files (can be seen using D2ResExplorer). but probably from DLG files. DLG required to correct text position for long strings.
If this is from .ff files you can try to replace that file - Rise of the Eves is almost same as GR for some of the files. better use D2RexExplorer that can extract and repack obj in some of the game files.