Go back to the ROM you had before and open it up with 7zip. And when I say go back to it I mean, the MyoldROM.zip you have saved on your computer, not to reinstall it on the phone. Choose "open archive". then go into the system/app folder. You will find your old keyboard in there. probably latinim.apk or LatinImGoogle.apk or something like that. Pull it off to your desktop.
Next.. connect your phone upto the computer and transfer the file over to your phone's SD card. Disconnect from pc. Now, using whatever you use, I use Root Explorer, go into your file you just put on your SD Card and longpress on it. Then choose "copy". Next navigate to the phones system/app folder and mount as R/W. Next paste your keyboard in there. Once you pasted it, go to it and longpress on it. select "permissions". Set it up so that in column 1, all three are checked, colum 2 just the top one and nothing in column 3. Once that's done mount back to R/O and reboot.
I am sure there is an easier way that takes 5 seconds but, this is what I know and I am just at least giving you a way to do what you want.