1. Not from personal experience, but this border has been open to EU nationals since mid 2011, many have crossed it. The border is called Kazbegi by the Georgians, and Verkhny Lars (Upper Lars) by the Russians... not sure how you got the Georgian version of the Russian border crossing.

2. While it is not possible to predict, the current situation has no bearing on Georgia, however Georgia must be watching very carefully.

3. Propose another route... always best just to say you are visiting Moscow and St P like a good tourist. Nothing is written on the Russian visa regards entry points or cities you may visit, I think this is a hangover from the USSR. No special permits are required to enter Ingushetia / Chechnya / Dagestan.

4. If you are concerned about safety, you'll want to stay out of Ingushetia and Dagestan, and take one of the more northerly routes via Budennovesk or Elista. It's a shame however as Ingushetia, Chechnya and Dagestan are some of the most interesting republics of Russia, and the city of Derbent in Dagestan is certainly the most interesting in the North Caucasus.

I only know the Vladikavkaz - Makhachkala and Khasavyurt - Atrtezian roads, both were OK. Maps of the region often mis-represent the main road between Makhachkala and Astrakhan - there is a left turn in Artezian which leads NW to Komsomolsk (for Lagan) and then to Yaskul, where one turns E to Astrakhan (or W to Elista). Roads are mostly pretty good, though sometimes not so smooth. In 2010 there were some roadworks on the Komsomolsk - Yaskul stretch.

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