Oh boy! The fun part of online diagnosis...
If you can't adjust your ignition timing to 10* BTDC with TE1 and E1 bridged then either your ECU or igniter is bad. It might be the capacitors in the ECU blowing. Seems to be a pretty common problem on these as they get older.
There are other less likely things like your crank pulley is damaged or TE1 or E1 isn't connecting properly (if your CEl is flashing they are connecting properly) or your cam timing is way off or somethings wrong with your distributor.
As I think someone else already mentioned, without TE1 and E1 bridged there's no set timing. It jumps around depending what the ECU sees. That's why you have to put the ECU into check mode, so it won't adjust timing.
IIRC there's more than 1 timing mark on the timing belt cover. I don't remember what degree the other markings are though. I guess if all else fails as long as you're between 10 and 21* at idle things are at least close to ok? I would definitely be concerned if you can't make it set timing though....
I do have one other suggestion. Since you have a 92, try jumping TE2 (yes TE2) and E1 and see if that gets you anywhere. Also, see if you have any codes while it's bridged. It also wouldn't hurt to drive around with it bridged to see if it comes up with anything (this puts it in a more sensitive diagnostic mode).