Please download this hotfix to address some bugs, see description for patch notes.
Changelog:
+Fixed a bug where domination counts could excede the maximum value of 16 (caused crashes on Linux)
+Alarm siren will now play at the beginning of arena rounds
+Arena will now activate points properly, with a 60 second grace period before unlocking (yes, this does fix the cap on arena_nucleus)
+Fixed spies being able to destroy their own sappers (needs testing)
+Engineers can no longer pick up sapped buildings
+Fixed players receiving assists on self-destructs
+Loch-n-Load attribute changed to 20% overall damage increase (from 20% to buildings only)