I've started a game with yesterdays nightly (6548) and it crahsed randomly a few times. These crashes seemed to get more frequent as i played with it. Then after saving the game once, the crash was there, but now not randomly...
The way to reproduce the crash:
1. open the save with the pak also attached (pak128 nightly with a lot of addons (i think in the game just one addon is used, but it was easyer to zip the whole pak)
2. Switch to public service
3. Try to enlarge the population of the current city (Makó) a few times.
4. Crash
Save: https://docs.google.com/file/d/0B1T_qBCnXlPdbWRWeDEtWU80N2s/edit?usp=sharing (https://docs.google.com/file/d/0B1T_qBCnXlPdbWRWeDEtWU80N2s/edit?usp=sharing)
Pakset: https://docs.google.com/file/d/0B1T_qBCnXlPdOHkxVHF6czRicmM/edit?usp=sharing (https://docs.google.com/file/d/0B1T_qBCnXlPdOHkxVHF6czRicmM/edit?usp=sharing)
Note: The first crashes happened to be random. I was doing as i remember different things when the game crashed.
thanks for the report. Should work again with r6550.