I have a perfectly working version of CS Cart Multivendor going, but my client is set on using the Booking Software available as an add-on. I am using the latest version 4.12 and they support up to 4.11. I have tested the software and it works, but it is causing errors in store functionality not related to itself. I am assuming that is because of the lack of compatibility.
Is it wise to downgrade so my client can use this add-on? If so, is a downgrade possible, or does it require essentially re-installing? Is there any other option for booking software out there that I'm not aware of?
There is no such mechanism. You can only request 4.11 distributive from CS-Cart support team and transfer some data with the export/ import feature. But please note that some data should be transferred manually in this case
I have MVE 4.13 and it also has issues with the Webkul booking reservation add-on. They are looking at it so might fix your issue too. I will post here once (if) they fix it, still got two weeks to get out and grab my refund so fingers crossed.
I have been unable to find another option, there is an event manager add-on that is more expensive and won't meet my needs but may work for you.
Update as promised: Webkul was unable to get their booking add-on working (despite for 3 weeks, multiple times a week they told me they would), they also didn't refund me (yet at least).
I have now purchased and installed the Ecarter Technologies (CS-Cart Booking System) and it seems to have better functionality, is cheaper (also currently on special, so cheaper again) and best of all it is working. It might suit your needs.
Thanks for this answer, I can only request 4.11 distributive from CS-Cart support team and transfer some data