If you have created a custom flag field in Project for the web, but do not see it as an available filter when importing into OnePager, this is due to a known limitation with custom fields in Project for the web. In short, while P4W allows users to create custom fields, those custom fields are not available outside of P4W, so are inaccessible to partner applications such as OnePager.
We have strongly recommended that Microsoft finish its work on custom fields in P4W so that our users can take advantage of flag fields as they have done in other versions of Microsoft Project previously. The best way to ensure that Microsoft takes this seriously is for our users to let Microsoft know how critically-important this capability is. Please join us in communicating this to Microsoft:
When you click the above link, you'll have the opportunity to add your vote to the request. The more votes this request gets, the more likely that Microsoft will prioritize it for a fix. In addition to voting, please also consider adding a comment so that Microsoft knows how important custom fields are to your adoption and continued use of Project for the web.
Last Updated: February 5, 2024