Isopropyl? Yes, there can be a problem. Isopropyl alcohol (isopropanol) is a big, smoky mess when burned in a Trangia. You generally will do better with ethanol or methanol (or "denatured" alcohol which is traditionally a blend of ethanol and methanol).

Isopropanol will work a little better for priming than as your main stove fuel, but either way I'd rather use something else.

This blog post on alcohol as a stove fuel may be helpful.

HJ