They still had tropical proportions but were roughly as tall as modern Negro people in Africa ~ and were clearly NOT white folk!
Remember, during the period of maximum glaciation in an ice age you have recurring periods of warmer weather where the ice may well melt allowing plants and animals to return.
Our early European ancestors supposedly walked into Europe about 35,000 years ago, just about when many of those cave paintings were being made. It is entirely possible that other people had gotten to Europe earlier, while the descendants of the San people in Africa (guys with the straight hair) simply arrived later.
The cave paintings I have seen pictures of are superb mostly realistic art. Nothing remotely comparable to them is being made by San or Andamanese hunter-gatherers.