1. Select NEW GAME > CREATE CHARACTER
2. Select Human Thief (either Gender, any Alignment)
3. Select minimum stats (3/9/3/3/3/3)
4. Proceed to SKILLS and allocate proficiencies to any weapon via plus button
No pips appear next to selected weapon but proficiency slots are spent (wasted). Slots cannot be recovered via minus button.
Pips should appear/disappear next to selected weapon via plus/minus buttons.
5. Distribute points to any thieving skills and click DONE
Character has no weapon proficiencies even though proficiency slots were consumed.
Character should always have weapon proficiencies.
6. Choose Appearance and Name, and finish by clicking ACCEPT
Death movie is shown after which screen stays black.
Game should start normally in Irenicus' Dungeon.
edit: As argent77 pointed out, this affects human thieves and bards with a constitution of 3.