I think you're using restorer and not 4012. Restorer creates a gross rubber reaction, not 4012
and for the record, the last time someone posted home brews they got blasted and I think the thread was deleted.
Createx restorer is 4008, and although it will destroy rubber o rings I doubt it will cause rapid drying of paint in the cup.
as for the previous thread relating to home brews being deleted, you're right it was, but only because the poster refused to listen to advise regarding heeding manufacture advise, and argued that he'd been doing it without issue.... and highly recommended its use.
People forget that a product (like windex) is designed for a specific purpose and the application there of is designed accordingly..... health considerations by the manufacturer are made with the assumption that you are using it for the appropriate purpose. The minute you use it outside of those parameters (eg, no longer use the supplied spray bottle but use it in a vessel that shoots out at 35psi and atomises at sub micron levels) the all their safety warnings become void.
EG: petrol will not cause major lung issues if you are just filling your car and driving. IF however you start sniffing it via a vessel that encourages inhalation then its a whole different ball game.
People are always going to try and experiment with consumables like paint/ reducers/thinners etc. but there also needs to be a sensible approach and the poster needs to be aware that they are on a public forum where people come to seek advise.
There will be a disclaimer created and added to any threads that mention a 'home brew' hopefully to avoid someone ending up in hospital with respitory issues.