The JPNZ owners handbook
http://www.amazon.co.uk/Mazda-Bongo-Fri ... 1869761561 has very comprehensive details, but here's a summary:
P - park - start engine in P
R - reverse
N - neutral - useful when stuck in traffic!
D - drive (normal driving)
S - limit to gears 1-3 - engine brake on steady decline
L - limit to gears 1-2 - engine brake on steep decline
Hold mode :
Hold+D - gears 2-3 - useful for snow/mud
Hold+S - gear 2 - engine brake or steep uphill drive esp. towing
Hold+L - gear 1 - strong engine brake eg very steep downhill
Hope this helps?
Simon