Damn, you guys are on top of it. This is all new to me so for those others in the dark, I'll post my original questions (to the G forum) here too;
"Sorry for the newb questions;
#1 The 10/11/12.5/15 measurements...is that with the (black ball) lever pulled out one, two, three or four "positions?"
#2 The KN(show kN in the above pic) measurement...I was thinking that was knots but 15knots = 25.32ft/sec which is WAY too fast for a winch from what I've seen. What what does KN refer to here?
#3 I translated the 7mm "wire" dia, 25m lenth, but what does the 2060N/mm^2(that's a pressure measurement) and 45KN calculate least breach power[rechn Mindestbruchkraft] refer to?
#4 What does the "6x19+1SES" style[machart] mean?
Answer from a G owner who works on a drilling rig;
#1] Typically, a winch it's maximum rated line pull is quoted with the first layer of wire rope on the winch drum. With every layer of wire rope spooled onto the winch drum your winch becomes less powerful. As a general rule of thumb; for each layer of wire rope on the drum you should deduct 10% off the rated line pull. The figures on your winch plate don't exactly match this 10% rule of thumb but this is where it comes from and as Bram_r stated it all has to do with pretty simple mechanics ... torque = length of the lever arm x force applied.
#2] 1 kN = 224.808943 lbf so 15 kN = 15 x 224.808943 which equals 3372.134146 lbf. That may be, as you've stated, not so much but still sufficient to help you out of trouble. Remember that there is such a thing as "double line" technique which will double your line pull but halve your winching speed by making use of a snatch block. Bear in mind that there's approximately 10% friction loss for every snatch block in use.
#3] The 2060 N/mm^2 refers to the minimum required steel wire rope grade. The term "Grade" is used to designate the strength of the wire rope. Plow steel- ,improved plow steel- and extra improved plow steel wire rope are commonly known grades. Tensile strength (resistance to lengthwise stress) ranges from 220.000 to 260.000 psi for plow steel-, 260.000 to 280.000 psi for improved plow steel- and 280.000 to 310.000 psi for extra improved plow steel wire rope. This means that the minimum required steel wire rope strength grade for your Rotzler winch falls into the EIPS wire rope category (2060 N/mm^2 = 298777,752428 psi).
The 45 KN refers to the minimum breaking load required for the steel wire rope in use. In other words, the steel wire rope should be able to withstand at least 45 KN (10116,402439 lbf) of pulling force before it breaks.
#4] The design of the cable, 6x19+1SES nowadays would be referred to as 6x19S+IWRC. A steel wire rope is build up out of wires, strands and a core. For the required wire rope this means as much as 6 strands of 19 wires each around an independent wire rope core. All this according the 'Seale' type of design for wire rope construction. I could go into detail here but that would be a bit much. Just do the Google thing."
Keep in mind this winch is 31yrs old now so it's a bit archaic technology.
Some more thoughts from one of the G guys;
"The Rotzler looks good and performs well, although extremely slow. If you want the original vintage look, it's the way to go.
If you want performance, go with something newer like a Warn. Warn is now the factory OEM."
I'm still torn on if I'll ever use it as a new 3pin controller (similar to a Ramsey) is $1300!!
Some of you Rover guys may find these pics interesting. A guy on a G forum has a Ramsey on his old Rover and it looks very similar to my Rotzler. So, we're not sure if Ramsey licensed the Rotzler design from Rotzler or vice versa;
Ramsey underside;

Rotzler topside;

Ramsey from top side on Rover w/ homemade solenoid box on left;


Since that Ramsey controller looks exactly like the Rotzler unit, I contacted Bob at Ramsey to see if they offer a 3pin controller (Rotzler is a 2pin connection). He suggested the #251110 Ramsey controller. However, upon looking at the pic of it's connector, it's a 4pin(1dummy hole) not a 3pin-only like the Rotzler's have.

Might you guys know of a 3pin winch controller? A pic of the 3pin connection on my Rotzler;

Factory NATO-style cable (ground) connector for those of you interested;

Connector on winch that plugs into the (ground) connector;

More pics on this thread if you're interested;
pointedthree.com/disc/forums/showthread.php