Yeah, UMD is a weird one. I'm pretty sure "1" isn't auto-failure, however it does remove that item from use for the rest of the day. Good thought regarding wands with 1 charge each. You can also drop them after using them and completely disregard them thereafter.
Discover a pit with careful probing, then hop over it.
Opening the door reveals the following room:Spoiler
Show
{table]|A_|B_|C_|D_|E_
1|||||
2|||||
3|||||
4||||B|H[/table]
There is a door at A-2, another at E-4, south side and another at E-3. There is a human wearing a chain shirt and holding a longsword standing behind a beast with patchy dark fur that covers its unhealthy shrunken black skin in some places. Open sores dot its hide and a feral, catlike head glances with it's blank eyes at the wall in front of it.
Initiative:(1d20+2)[20]
Edit: The human motions to the beast to "stay", then readies an action while motioning for you to leave.