I use two computers at work, and I have a roaming profile. Can I install/use your product on one (or both) computers?
Yes. Each machine installation is isolated from other machines, but the license is issued on per user basis.
In sum, NumXL can work with any user profile type (i.e., Local or Roaming), and you can use NumXL on both computers, as long as you are the exclusive user of those machines.