I'd add the following comments as regards snow driving, which are not really Renault 4 specific, but might be useful:
1/ BEFORE driving off, make sure your windows are clear and that your car's lights are in good order. Don't rely on your car's wipers and demister to clear them; they'll keep the windows clear once they ARE clear, but might not clear them to start with. Make sure your screen wash bottle filled with a non-freezing solution.
2/ Accelerate and brake G-E-N-T-L-Y at all times and try to keep in as high a gear as possible. This reduces the torque delivered to the wheels and makes the car less likely to wheel spin.
3/ Slow down before cornering more than you normally would, as the forces acting on the car will not be as easily restrained by the tyres. Indicate clearly.
4/ (Odd one, this...) Keep the car radio OFF and open the windows at junctions. Cars make less noise when driving on snow, so listening carefully you're more likely to hear the crunching sound of car tyres on the snow.
5/ Make sure your mobile's fully charged.
6/ Carry some old sacking in the back, to be placed under the front wheels to get you rolling if you are stuck. Attach lengths of string to these sacks, and tie the string to the door handles before driving over the sacking. This will avoid the need to stop and recover the sacking and allow you to keep going until you're on terra firma before picking the sacks up! A spade's handy too.
7/ Wellington boots and a really warm coat in the passenger compartment, not in the boot, so you can easily grab them, instead of having to get out of the car in freezing conditions to put them on!
Good luck......