The Rapid Fire ruleset makes no special allowances for wargaming this theatre. It is indeed unique in terms of scenery and way the environment affects warfare.

The tank battles in the western desert book by Donald Featherstone gives some very good ideas regarding terrain, and visibility.

The main issue which he discusses at length is the problem of dust, I suggest this gives us the following spotting rule ( which he develops further with spotting distances at different times of the day );

Single vehicle moving ( dust cloud ) 30 inches
A group of vehicles moving ( dust cloud ) 40 inches

He also discusses the tactic used by the Germans of attacking in the evening when the sun was setting ( in the west ) behind them, which gave the allies some problems.

In terms of spotting ;

vehicle stationary - 5 inches
single afv moving ( dust cloud ) 10 inches
group of AFV's moving ( dust cloud ) 15 inches

Further rule ideas for desert RF battles

1) Lack of tarmac roads - most roads were trails that were hard wearing on afv's, hence only really main roads of which there would be very few would be allowed the full on road movement.

2) Mirages - halve spotting distances

3) Rommel - If the Field Marshall is in your order of battle, add plus one to all morale checks. If Rommel is killed, deduct one from all morale checks.