Projectile file modding

Greetings,

I am new to modding the M2TW game. But like the game itself, modding is addictive.

But my newness brings with it the typical problems and less typical questions.
Here are a few related to simple mods of the projectile file in the data folder. BTW I am using SS 5.1 for my base game, but that makes no difference to the q's I ma asking...anyone who is a modder can help me.

After making some changes to the mass, radius and area of the mortar, I saved the changes and ran the game to test. But I got a lateral trajectory, so I decided to go back and make one change at a time. So I put all the original numbers back in the file, saved it and rebooted the game. The first time I rebooted I got a total recovery and the game worked as before I did any mods. But the second time I restored all the original numbers by pasting the section which includes all of the lines from 981 to 1009...and rerunning the game, I got the same non-mortar "cannon" type horizontal trajectory!?

So I retried the pasting, of course using the original descr_projectile.txt lines, as before. But now I seem to have somehow ruined that file too.

In taking a more careful look at the files, I also noticed that the "date accessed" detail on the file is not accurate..off by a few minutes...2 or 3.

So now I am wondering if I am doing something wrong when I save the files: both when I am running and change, and when I have restored the original data. These data are only three lines, but I am at a loss to see what I am doing wrong.

BTW some changes I made several weeks ago continue to work OK. Examples are: increased accuracy, area, and damage effects on many cannons, bombards, and other projectiles.

Any help will be greatly appreciated.

Thanks.