I wrote a millisecond to tick convertor app a while back. You are welcome to it.
It ran fine for most people.
http://audiomastering-online.com/stuff/MusicCalc1.zip
Extract and install.

I didn't include converting it the other way, but I could.

You would input the number of milliseconds you wanted and it would tell you the number of ticks to add when you pasted it .. but you'd have to enter the Tempo and Resolution being used in order to calculate the ticks. Might be fun to revisit that program.

I figured people could use it 'as is' to know the delay in Ms to make something echo on the beat (or half beat). Looking at it from the reverse path, I suppose it could be useful too.
Been a while since I programmed anything that wasn't web-based, so it could actually be fun. My goal when I set out was to make a calculator for digital musicians. This may be a good next step for it.

I do not work here, but the benefits are still awesome
Make your sound your own!