Hi,
we are actually evaluating CS-Cart (Trial) to check if it fits our needs and it looks really promising!
I need to customize the SEO urls a bit further than the backend settings allow…
I would like to keep the SEO add-on untouched and only make some minor changes to the generated url output. Didn’t find something about that in the forums…
So is there a way to partially override an add-on? Any way to add a hook to an add-on?
Or is it not necessary because there is a hook at the core which could be used?
Any hint would be much appreciated!
After some code research I got it… the hooks system is pretty plain and useful 
Didn’t know about the ‘stack’ and that add-ons have their defined priority.
The hooks base is a nice tool! (https://www.cs-cart.com/api)
And a ‘grep’ over all source files reveals the exact positions of the hook points (just looking for function calls ‘fn_set_hook’).