1) BvM seems to have a penchant in the even numbered races for highlighting the Christmas season in Central Europe. Starting with TAR14,WRP started filming the race in Nov/Sec for even numbered races.
22 -- Alps Interlaken, Suisse and Berlin
20 -- Alps Torino and Fussen
18 -- Alps Vienna to Salzburg to Zermatt
16 -- Hamburg and Champagne District, France
14 -- Alps Locano and Interlaken, Suisse
12 -- Netherlands, Lithuania, Croatia, and Italy (but this was filmed in summer, not in the Nov/Dec timeframe)
2) BvM also likes to put teams on trains and self drive when in Central Europe. It seems we usually get about a 50% success rate on spotting teams on trains in Europe.
So here is my analysis and speculation.........
Leg 7 is Rome
Leg 8/9 Train from Rome to the Alps (ether Suisse, Bavaria or Austria). It is easy to get to either western or central Suisse or western Austria from Rome. Possible self driving in these legs.
Leg 10 is Seville, Espana
Leg 11 Since they flew from London to the end city (Las Vegas), they probably did this leg in the UK somewhere.
Leg 12 Las Vegas