Well I am about to give up on the cheat menu. I have added a batch file to the config file but it doesn't work correctly.

here is the batch file I used.

ULTIMA7 ABCD 

Has the alt 255 on the end of it. I used the number pad for the 255. I wonder if I should use the normal numbered key instead of the number pad. I will try that.

I did go to teh cheat room at the blacksmiths shop but when I got to Minoc the murder scene would disapear when I walked into the sawmill.

Help please.

I am not entirely sure, what your question is, tbh, but I'll try to be of help nonetheless ;-)
Cheat mode: to enable it, you need to start the game with the ABCD(ALT+255) suffix like you said. It is vital to use the numpad ONLY...NOT the normal numbers.
If you have started the game in cheat mode, you can access it using F2. Also F3 is available then, which will bring up the map with a crosshair indicating your postion.
If you fail to make it work, you can still resort to using the Ultima7Hacks by JohnGlassmyer, that allows to enable and disable cheat mode within the running game.

This said: none of the above is in any way related to the cheat room you mentioned and neither to the murder scene...

You can try launching Ultima manually with ULTIMA
This is ULTIMA with a single space, followed by ALT+255 which should type another invisible character. Your situation in Minoc is an unfortunate bug. You can read about it here: https://www.gog.com/forum/ultima_series/minoc_murder_scene