The height of the Message/Log panel is too much, and currently I should resize it everytime when I run TeXstudio as it is reset to default once TeXstudio is closed. Is there anyway to adjust and fix its size?
Which version of TXS are you running? This sounds like an issue we had earlier. The current 2.6.6 should have a reasonable small default log panel height (except maybe on very small screens). From the upcoming version 2.7 on, the height will also be remembered for the next session.