Well, I tried about a dozen themes in different sizes. The slider and slider-touch images do not appear to scale correctly in the old themes. This makes swipe to flash or unlock impossible. Until a custom theme is found that is not broken by the new scaling, I'll Just use the default theme. No problem.
Sent from my SAMSUNG-SGH-I717
EDIT: I just checked & I do NOT have the new twrp theme flag in my source. I doubt it will help but I'll compile it with the flag set. I will link you the build to try since I have never themed twrp or any recovery as far as that goes. lol
And here ya go TWRP_quincyatt_TW_THEMES_flag_test.zip
ATTENTION: I have NOT flashed this myself but I am certain that @developweb can fix any issues if they arise. This is a TEST build ONLY!! Please let me know the outcome & if I need to try a different flag? I used
TW_THEME := portrait_hdpi
And the selections are as close as I could come I believe.
* watch_mdpi: 320x320 * portrait_mdpi: 480x800 * portrait_hdpi: 1080x1920 * landscape_mdpi: 800x480 * landscape_hdpi: 1920x1200