I have never tried it myself. Do you know why it was taken up? When you say most still has the foam backing that don't sound real good.

On the other hand you are not out any money if it doesn't stay together. I would dry lay several rows to see how they fit. You also will need to acclimate it to your inside environment.

If the padding is off the back don't use those pieces. They are not the same thickness as the good ones. As long as the tongues and grooves are in good shape and they inter-lock tightly when you put then together they should work fine. That's one nice thing about snap-together laminate flooring is that you can take them apart and re-use them.