I'd like to buy V3.5 but will need the V2.6 version to fix a client's project that uses V2.6 . Does anyone know whether I can still download V2.6 and get a licence file. Is it standard, or do I need to make a special request? The reason I'm asking is that the change required is urgent (before noon 27 March, EDT (Montreal time)).

If you buy v3.5 you have access to older version's downloads. You need to request a v2.6 license by opening a HelpDesk thread and providing your Customer ID.

(Edit) Followed at HelpDesk