maybe a combination of your snippet / @EVAL call with checkboxSortable (http://modx.com/extras/package/checkboxsortable) could also be a solution to your problem...I actually have issues with the active checkbox not appearing in 2.2.6 (but in 2.2.5...) but there's not a biiiig difference between this and migx, just the setup is maybe easier because you would just have to set up the tv once with the snippet call, then create users in user admin area and you're done instead of adding the users manually to the migx grid...tell me if you try and if you're on 2.2.6 too, I would be interested in you having the same bug as I do? (acutally it goes away when resizing the browser window)
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