Condominium trustee telling me I must take down a sheet on the front windows as I wait for drapes to be delivered - legal?

Difficult to answer without knowing what the recorded condo trust, bylaws and rules and regs of the association say. They are typically not amendable upon the whim of a trustee. Typically there is a dispute resolution clause where a neutral decides these issues if they cannot be worked out. They need to provide owners with copies of the governing documents (or at a minimum allow you to inspect during normal hours), so you should start there.

I agree with Atty. Brooks that this question is difficult to answer without seeing your actual condo documents and the dos and don'ts they contain. You should sit down with a local attorney with those documents. Usually, an initial consultation is free. I further agree, though, that a single trustee cannot unilaterally change rules, but then again nor can one in the past have allowed you to garden on condo common area unless the rules permitted it as an exclusive use common area. Outside railing are often part of condo area, and things hanging on them are often regulated, so there is one instance where a check of your documents is needed. As for the inside of the unit, generally that is yours. Many times condo rules restrict things like signs or political banners in windows, but they cannot dictate your choice of draperies on the inside of your unit, especially where your current choice is temporary.