Hi,
The z_module_indexer maintains an index of which templates, actions, scamps, filters etc are available on your system.
For this it crawls your site, site's modules and zotonic modules.
So, it is quite essential in the functioning of Zotonic :)
When you enable the mod_development then it will ping the z_module_indexer periodically to check for any changes.
On systems with many sites this might actually slow down the sever a bit.
The search queries module, mod_search, provides almost all searches for the rest of the system.
When you disable it you won't be able to do a lot of searches.
That is also why you see those notes about unknown search queries.
The dashboard can't be changed at the moment.
I would love to have a configurable dashboard!
- Marc