Apriori, without having looked at all at the Orbis sources, I'd say it's most likely too much python code doing too much work. Every time the engine has to bridge between the dll and the python code a lot of processing time gets used. If new events are added which get triggered alot this can slow a mod down. Further, python code runs quite a bit more slowly then the comparable algorithm in C++.
Beyond that, it may be there are some run away algorithms in the mod, but without profiling or benchmarking tools (or a detailed understanding of the mod's codebase), we'll never find them (unless they're obvious, in which case I rather think Ahwaric would already have found them).
Beyond that, it may be there are some run away algorithms in the mod, but without profiling or benchmarking tools (or a detailed understanding of the mod's codebase), we'll never find them (unless they're obvious, in which case I rather think Ahwaric would already have found them).