The GLINTBTCHNUM is populated if the entry had already been picked up for the GL Posting (interfaced to GL already).
There's really a lot of things that need to be discussed on integrations, regardless of what you use. For example, when you integrate to the Asset General window, is the auto add to book option marked (don't remember the exact option as I don't have GP opened right now).
Once you save the asset , the 'account group id' becomes irrelevant as the specific GL accounts will be attached to the asset record itself.
And those accounts can be changed anytime.. if the account group id is saved or attached to the asset, but the specific GL accounts are 'allowed' to be changed over time - the account id may be a source of confusion if the said changes actually happened.
For example, if you have a group of assets you consider as 'Equipment', you assign the asset group id 'equipment' with specific GL accounts signifying equipment accounts, say for clearing, for cost, etc... over time, one of those accounts may need to be changed for some reason (like the business needs to inactivate it or change it for reporting purposes)- then identifying the asset by the asset group id will no longer be reliable.
I really cannot give a specific set of recommendations on re-uploading unless I see the data.
I am just saying, instead of identifying the assets with issues one by one and fixing the issues within GP - I think it will be easier to fix the issues/missing or incorrect info in an Excel sheet, validate it etc.. then remove the current data in GP, and reupload...
Again, you can communicate with me directly as it may be easier...
