Fozzie
A catch-all is a POA which allows the holder to do anything at all in regards to the property, as opposed to one which specifies exactly what is permitted; in a "normal" POA obviously anything which isn't included is automatically excluded. The problem with a catch-all is that the holder may be able to do ANYTHING at all, including opening/closing/using bank accounts, signing contracts on your behalf or even selling your property - that's not to say that they
will but they may be
able to.
It's a VERY good idea for you to re-read the POA you signed very carefully and to decide if you should arrange to have it rescinded as soon as possible.
Likewise you need to re-read the preliminary contract (and check that the Bulgarian version, which is usually part of it, is identical in content to the English version - the Bulgarian one will take precedence). Most preliminary contracts I have seen include clauses on the size and timing of staged payments, and exactly when they are due. This is usually after the various Acts have been issued and it's normal for a copy of the Act to accompany each payment request. If you have paid based on an assurance that a certain Act has been issued and this proves not to be the case then the developer is in breach of the contract.
Since I have no idea what is in the preliminary contract, I really can't comment on what you are or aren't committed to but it's extremely unusual for anyone to pay maintenance on a property which they don't even know if they own, for "services" which aren't set out in a separate contract and on a complex which hasn't held an AGM to appoint/ratify a maintenance company. The comment you made about not permitting access to renters seems to indicate either an attempt to brow-beat "owners" or evidence that the contractual situation is more complicated than you think.
In a lot of ways you're actually quite lucky: at least the complex exists and the developer hasn't done a bunk with your cash or, as far as we know, sold it to his wife for 10 leva. Moreover, they do still seem to be reasonably committed to the project.
There's one other factor you might care to consider and that's the possible effect of a collective action by owners. On the one hand, there's safety (and power) in numbers and the developer might well become more reasonable when faced by a large and united group; on the other hand, a class-action might cause him to cave in financially and to declare bankruptcy, leaving everyone with years of expensive legal action with nothing to show for it but some well-fed lawyers. It's possible that the correct amount of individual pressure, applied in the right way, could lead to a result which you personally might find acceptable; I guess it depends on how you feel and whether you believe in the financial survival of the individual or the species...