As for captured Italian guns, they might have been 100/17 howitzers, which seem popular at that time in North Africa.
To finish with 1939 armoured cars:
569 Wz.29 Ursus - they were built and given to the Army in 7/31 (now 1/30).
Speed could be 12 (35 km/h - now 11) - same for units 574, 671.
Armament of all wz.29 cars should be IMO reduced to gun and one TMG only.
The car officially had three MGs in the beginning, but a BMG was rear-facing, what made it useful in peculiar combat situations only.
The remaining three weapons (gun, TMG and AAMG) were manned by a commander and mounted in different sides of a turret, what made quick change of weapon difficult. As for AAMG in an upper ball mounting, it was inefficient, and quickly removed (more:
http://derela.republika.pl/wz29.htm)
The first unit 569 could have AAMG instead of TMG, because it had some chance of downing a slower aircraft of that era. In next units it should be TMG.
I'll attach alternative pictures.
570-572 Wz.34, Wz.34 I, Wz.34 II (variants with MG and early camo) - in my opinion, distinguishing between these models doesn't make much sense. They mark only mechanical components, weren't usually used, and can't be associated with either of two types of armoured hull (more:
http://derela.republika.pl/wz34.htm).
Wz.34 I is completely redundant - no external difference, nor in specifications, not distinguished from wz.34 II in official statistics.
Wz.34 II was newest model, but according to a military manual, it was in fact a bit slower (50 km/h) than wz.34 (54 km/h) (now wz.34 II has 18, rest - 16). IMO, its speed should be 17 (=51 km/h). It could be merged with wz.34 and named just "wz.34", or we could keep both, one with a picture with old hull (vertical rear) and one with newer hull (slanted rear).
BTW: the picture 29521 of #571 has late camo, while it's supposed to have old camo.
575-577 Wz.34a, Wz.34 Ia, Wz.34 IIa - as above (variant with 37mm gun and late camo). There was no designation with "a" for a variant with 37mm gun (or any other special designation). It might be named "Wz.34 (37mm)"
674-676 Wz.34a, Wz.34 Ia, Wz.34 IIa - as above (variant with 37mm gun and early camo).
Picture 29519 shows cars in late camo, while it is supposed to be early camo. I'll attach a photo of the car with gun and early camo.
678-680 Wz.34, Wz.34 I, Wz.34 II - as above (variant with MG and late camo).
If we'd like a photo, a proper one is in fact 29521 (used for early unit 571)
Michal