I don't have the game so.... Searching the forum here for Theme AND Park indicates that several people has got it to run. So.... Back to basics:

How did you install it (mount settings please)?
Tried configuring without sound?
With all sound devices turned of the DOSBox configuration file?
Tried the LOADFIX command?
Tried changing CPU cores?

Thanks for your reply, this is the first time I have ever tried to play an old game with dos, so please bear with me..

I used the commands

MOUNT C C:\OLDGAMES
C:
CD THEME
MAIN

The game loads fine, I didnt change anything other than using Ctrl + F11 to slow down the frames to 5% as this is the playable speed..

I dont understand what LOADFIX or CPU core is, so if you could talk me through trying them that would be very nice of you..

I also have not tried any of the sound cinfig you talk about either, how would i do this?

Start by locating the file dosbox.conf. It should be in the same directory as DOSBox itself (C:\Program Files\DOSBox-0.72 or something similar).

Make a backup!

Next open the configuration file with Notepad.

Inside locate the line where it says cycles=auto.

Change it to some low value like 6000 and see if that slows DOSBox down enough so you don't have to fiddle with CTRL-F11.

The LOADFIX command is described in the README file that is also in the DOSBox folder.

Changing the CPU core is also done inside dosbox.conf. Just read the comments in dosbox.conf.

Sound config... When you installed the game, was there no instruction for choosing what kind of sound hardware to use? SoundBlaster, Gravis Ultrasound, Adlib ??? Is there a SOUND.EXE, SETUP.EXE or something in the THEME directory?

Thankyou very much, I changed the cycles=6000 like you suggested and it works fine!

Your help is very appreciated, to speed it up slightly would I just change it to 6100, 6200, 6300 etc. until it is at the speed i want?

And one last thing, if i change the game to full screen the graphics distort and the colours change, is there anything I can change to make the full screen the same as when the game first loads?

It is playable as it is now, but fullscreen would be cool.

You could try different output methods (surface, overlay, opengl, ddraw, ...) and see if the colouring gets better. Or change windowresolution.

Also, maybe start using one of the DOSBox frontends. Makes it easier to configure all this stuff.

i have another problem. when i try to start (d:\theme hospital)
it says:
heap allocation failure
(Reason code: 2)
any ideas?

theme hospital isn't theme park

i searched for sound bug posts... this was the only one