When switching between the three UI presets, the Custom HP Bar setting no longer saves, and has to be manually toggled on and off. For example, if Preset 1 has Custom HP Bar toggled off, and Preset 2 has it toggled on, swapping from Preset 1 to Preset 2 doesnt switch the HP bar any longer, forcing you to go into the Edit UI settings and check the box. 

This is a known issue. You can find the list of known issues here:
https://www.naeu.playblackdesert.com/en-US/News/Detail?groupContentNo=184&countryType=en-US