Fantastic mod!
If the game crashes when entering a city, the cause is a vanilla landmark already exists in that city.
To fix it you must:
1. Remove the plugin temporarily from \Documents\SimCity 4\Plugins\
2. Destroy any vanilla landmarks
3. Save and quit
4. Add the plugin back
5. Re-add your now modded landmarks.
Problematic regions with vanilla landmarks include:
- Timbuktu (tutorial region)
- Maxisland
The good news is that if you remove the plugin, any modded landmarks revert to their vanilla counterparts without crashing the game when entering a city, so the mod is safe to use.
"4. Download the latest mod collection here, using these three files"
The collection has more than "these three files" what about:
COT Crossover All Roads-mod.zip
Crossover All roads-mod.zip
Project_Orion_3k_Extended_Boundary-mod.zip