That sounds like something wasn’t right with your SKSE installation. Version mismatch? Files in the wrong places? A conflicting file somewhere?
For help diagnosing crashes, post the crash log in a pastebin or gist! SKSE should write logs if it gets far enough along. And for crash logs from SKSE plugins, use this crashlogger.
The EasyNPC discord server has a channel for preview requests and a channel full of fulfilled preview requests. This was pure gold! They also have links to all the tools they use for making consistent mostly-automated previews if you want to give it a shot yourself.
IIRC it’s linked from the mod page.