BIML generated SSIS package won't load with error 0x80070057 "The parameter is incorrect." CPackage::LoadFromXML fails

I have generated several packages with BIML but none of them load into the SSIS designer. Every one shows a white screen with the error message: Error loading 'Stage_BNSCHED.dtsx' : The package failed to load due to error 0x80070057 "The parameter is incorrect.". This occurs when CPackage::LoadFromXML fails. I can't even figure out where to start on this one. The BIML script will compile just fine and the packages are created, but I can't open them. Also, Visual Studio won't let me save the project or solution because of this error.

• BIMLExpress 2019 Build 5.4.64108.0
• SQL Server Data Tools for Visual Studio 2017 version 15.9.21
• SQL Server 2017 Standard Edition 14.0.3281.6

Appreciate any suggestion on where to start.

As I removed pieces to find the offending section of code, I came across the problem. I was attempting to do an update in an OLE DB Command, where I was updating a key value that was also in the WHERE clause. Once I rewrote that section to only list the non-key fields, everything worked as planned. I think technically that's legal in SQL but SSIS sure doesn't like it.