All Modded servers are affected by the hotfix to Patch 37. Until FunCom do another update (likely to the DevKit), no mods can be reliably updated. Perhaps FunCom have a cunning plan as to why the ‘canbeplaced’ code and master placeable causing the issue were changed?
If you test just loading up only the PIPPI mod for example (do on Solo of course and post a backup if you have a solo game ongoing). All appears to work till you try placing any of the ten or so PIPPI placeables. You will get a Fatal Crash.
As no other mods are loaded, and you will get a Fatality if you try placing anything from any mods with placeables, then technical fault diagnostic process flow points more to the use of any mods or the core game no longer being compatible with mods than with any specific mods.
I have seen that all of the Modders for the major-player mods are now awaiting FunCom on this. Therefore all server and their respective players, will not be playing Conan Exiles till updates are done - a day/weekend of rest ahead perhaps. In my irrelevant opinion, this might be an excellent communication opportunity for FunCom to grab a cuppa cocoa (beverage of choice) and then send out a general comm stating that (a) there are indeed issues; (b) the issues are being resolved; © there will be continued feedback during the day; and (d) we are very sorry that this has happened.