Have you talked to the director about your concerns at all? It sounds like they need to start making decisions.
If the director didn't address these concerns when you brought them up, I would go to the producer(s) and have a really frank discussion with them about the situation (again) and lay things out for them clearly and in no uncertain terms- that if certain decisions aren't made, you won't be able to tech the show. (At this point, I would go to the producer regardless of what the director says- they need to weigh in).
If you've only been talking to one person in the administration, like the PM, it's time to get other people involved. Bring up the points that you've mentioned here:
1. When is the script being frozen?
2. When are the costume designs being decided? At this point they have to be something that can be executed in the time you have left.
3. You can only call the actors for X hours- what's the plan to get you to tech? Mention the fact that the actors are not memorized.
4. What is the plan for tech?
My sympathies- this is a crappy situation to be in. I was the SM for a new musical once that had the same kind of problems. The show was completely rewritten the day before tech- and how do you tech something that you've never rehearsed? We ended up rehearsing instead of teching, and the designers wrote cues on top of rehearsal. In terms of triaging, that might be as good as it gets. We also ended up canceling a couple of previews. Cast morale was terrible, and I thought some of the actors were going to quit. (The show was a mess, despite being a really interesting idea with very talented performers, and ticket sales were so bad that we closed a week early.) Ultimately, despite having a good history with the company, I didn't feel like they supported the production and didn't involve themselves in the issues, even when I brought them up. Not a place I wanted to work after that.