Unfortunately no, the enemy list and the maintained spell monitor both use composites to display the icons/tiles, so the only choices are vertical (down) and horizontal (left to right). The
Darq Side version of the maintained spell monitor got some internal upgrades recently, including changing the composite to a volumepage. So making it fill bottom to top is possible there (line 204, change left2right_down to left2right_up).
As far as the lag goes, when you get updates click on the gear icon next to Maintained Spell Monitor and make sure "Lite" is checked. The old standard version has a lot more features, but one of them is incompatible with an internal game change from a while back and causes a noticeable stutter. While you're there, you can also check the Browser and make sure it's also set to Lite. That's the default choice for both of these windows, but check under the gear icon just to make sure.
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