First, your Text Box, when you have this kind of issue... it's because its size is not correct.
try to make it larger (or smaller), it would work better:
Now, for the strange colors in your HUD. It's because the game engine loads 2 screens at the time: the current screen and the screen next to it... and the attributes of the HUD areas are mixed.
So, a easy workaround:
On your 1st screen, paint the HUD area with the "R" key (hold the "R" key of your keyboard to paint the area with the Sub4 palette)
AND, on the screen next to it (at its Right), ALSO, paint the HUD area with the "R" key (sub4 palette) :
It should fix your issues.