Easy Way To Find Occurrence Of An Instrument In Song?

Like a search function that would bring you to the occurrences of an instrument in the pattern editor?

Currently there is no such thing.
The other way around is possible:let Renoise auto-select the instrument at the (nearest) position where the cursor is.
If you would like to remove an instrument, there is a function in the Edit menu where you can tell Renoise to remove all instruments that are currently not being used.

So “jump to nearest occurence of this instrument” would be the logical counterpart to it.

Sorry, not sure what you mean by this. How would I do this?

Yep, actually that’s the reason I was looking for a search function, I deleted all unused instruments but there is one still there I have no idea where it’s used

press shift+return.

What Johann said or if you want this automatically done, check this box in the player control panel:

Aha, you used an instrument somewhere to test but you don’t want to use it anylonger and now you don’t know where you filled that one in…

Okay now this is what you can do:
-open up the advanced edit
-click whole song radiobutton in the top of the advanced edit area (bottom radio button ofcourse)

-Now scroll down to the instruments section in the advanced area
-Select the instrument-number in the source that you don’t want to use anylonger
-Now click the delete button.

If all goes well, your instrument should be deleted if you now click “delete all unused instruments”