You can download the latest SVN-Daum Dosbox from January 2015, unpack it and replace the original Dosbox folder (don't forget to include the GOG Graphic Config utility).

Here is a screenshot with the latest Dosbox version:

http://www.mujweb.cz/nakamura/gfx/redguard.jpg

Moreover, there are some settings that may or may not have effect, edit them into the dosbox_redguard.conf file:

output=opengl
cycles=max
cputype=pentium_mmx
voodoo=opengl

Moreover, this version uses the obsolete version of nglide wrapper (1.03), upgrading to 1.04 might be advisable, though I cannot say if it brings any practical benefit.

Is there a safe link for the download?

Thanks!

It's listed on the SVN Builds page.