George,
I have a table with more fields, formula fields, and relationship fields than you describe, and just created a new pipeline for that table the day before yesterday.
Based on that, it seems unlikely the number of fields is causing your inability to save. If there was such a limit, support should be able to tell you how many fields of each type are allowed (and that reason should be displayed in the error message vs. a random internal error).
How many pipelines do you have for this table?
------------------------------
Gretchen Jorgensen
------------------------------
