Re: Spreadsheet
hi gm, and welcome to Tikiwiki comunity 😊
Former Spreadsheet feature in tiki is working again tin Tiki 4.2 and 3.5, and you can use javascript functions, as far as I remember (and I recall reading that documented somewhere in the Documentation of pages related to Spreadsheet pages.
New Spreadsheet interface in Tiki5 will use Jquery sheet, which has its own functions, afaik. You can read the documentation for JKQuery Sheet (linked from Tiki5)
I hipe you can help us improving that part of the Documentation related to the new Jquery Sheet interface and its functions, etc.
By the way, you might be interested also in (dev:PluginR)), where you can use all the power from R-project.org.
Hope this helps
Cheers