Hi David
In general, Studio captures that information in the script. You can click on Synchronize in the MAP tab in case you swap systems or manually adjust the script to read the attributes based on the field names from the SAP system you are connected to:

Given you are using something custom, you can check the max length it captured in SAP by drilling into the details of the field
- position cursor on the field in the tcode
- click F1
- click technical information on top of the pop-up (looks like hammer/wrench)

- then double click on the field name

- You will see something like this:

And as you found, there is no way to set/adjust the max length. IDK if that is even possible, but perhaps you can create an Idea on the Ideas portal to have it considered:
https://ideas.precisely.com/?project=AUTM
Best Regards,
Sigrid
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Sigrid Kok
Precisely Software Inc.
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