We are continuing to work with Salesforce on this issue. Salesforce has reproduced the issue successfully and escalated this to their Teir 3 team. Please note that this is only occurring in sandboxes that have been upgraded to Salesforce's Spring19 preview. A work around to this issue is to remove formula fields from the SFM page layout using the SFM Transaction Designer. We will continue to post updates as we have have them. Currently there is no ETA on resolution.
Thanks for the update but know that the workaround doesn't work if you are using the field as part of the filter or process in the SFM so we are on a holding pattern until a solution can be found. Joe Borgstrom Charles Miller
We're are also having issues in our Dev sandbox showing "Exceeds maximum length..." when attempting to save the SFM transaction, but works fine in our Full Sandbox. Both are on SMAX v17.3 and SFDC Spring '19.
We have received the following update from Salesforce. The expect to have this resolved by Wednesday evening. We will continue to post hear as we get more updates.
"The behavior with the "Zero Length Formula Fields" in the Spring 19 release Orgs has been confirmed as a Known Issue by our R&D team. Please find the below Known Issue Link an dclick on the button "This issue affects me" for further notification on the Bug Fix.
Starting in Spring \'19, doing a describeSobject() on an object that has a Formula Text data type yields a length of 0 for that field.
Before Spring \'19, Formula Text data types had a length of 1300.
Our R&D team is working on high priority to fix the bug and tentative fix for the patch release is expected to be tomorrow evening most probably."
Salesforce has informed us that a fix for this issue will be rolled out on 1/10/2019 5:00 PM PST(Safe Harbor). Once the fix is rolled out we will test and update here. We will continue to monitor this issue and provide updates when available.
Fix was applied by Salesforce and its working in all the ORG's where the Spring'19 was updated.
Just an FYI that it doesn't appear to be in all Orgs yet. I still have one sandbox that is on the original 4.0 patch and not the most recently applied 4.1 which resolves this.