Lars, The first rule of boot fitting is to never go up or down a size shell to make the boot fit. Find the correct length of shell and it either fits or it does not. The Alien Rs is a much narrower boot than the Gea Rs. So if the Gea RS was to narrower than the Alien RS will be worse.
Victor I would say do the same size in an Intuition Pro Tour liner. For your foot the low volume liner would probably be a good choice. Warmth is a function of blood flow more than foam. So having a good fit with proper blood flow will be warmer over any thick foam.
Piotr, I just measured the 25 Protour liners to one of our 25/25.5 stock liners and the Protour was a little longer again. The 24 Protour is the same length as the stock liner. Generally the rule of thumb is matching the Protour to the stock liner and if they are the same length then the volume will be very similar after molding. You would just use the Medium Volume over Low Volume depending on the amount of room you need to take up. Although with that said the Low Volume liner will snug up the fit over sto...
Alex, In general there is always some lift in race boots. Blistering is not good though. We have not tried another liner in that boot yet. It sounds like you have tried everything we would have, it might be that this boot is not the right fit for you unfortunately.