I had a tag I downloaded. It gave me the error can't add this tag. I exited sapien, and when I came back, sapien would open to the open scenario window, but regardless of the scenario I open, it crashes after I select a scenario. Removing all custom tags and reinstalling the HEK had no effect. My other computer complains about not having enough memory every time I try to run sapien on it, so I am out of options.

Open debug.txt (located in the same folder as sapien) and copy and paste the last entry here.
It should look something like below except with your errors:

04.26.16 13:56:18 sapien pc 01.00.00.0609 ----------------------------------------------
04.26.16 13:56:18 reference function: _write_to_error_file
04.26.16 13:56:18 reference address: 401b13
04.26.16 13:56:18 Couldn't read map file './sapienbeta.map'
04.26.16 13:56:20 CreateDevice succeeded with refresh rate = 0
04.26.16 13:56:21 Increasing sound decompression buffer size to 1048576 bytes
04.26.16 13:57:03 local player 0, weapon (0x0), deleted unexpectedly

My sapien does not record its errors for some reason. My debug.txt file exists, but it only contains a list of errors created by tool.exe.

Dang it.
You know, normally I am the smart one with computers in my family, even in my extended family, but this game is turning me into an idiot.
Thank you.

Just post the last part of the debug.