i was able to UP A/Watts. could only do it with connecting laptop to Baserunner controller - manual says it can all be done via CycleAnalyst, but couldn't do it that way.
The CA can only change CA settings, it has no communication with anything else to be able to change their settings, and no software to know what to change or how to change it.
So the reference to changing these with the CA is only for changing the limits within the CA itself, as it has it's own A and W limits if you are using them.
Normally if you have a controller with a programmable limit set, *and* the CA, you should choose which one's limit set you are going to use, and then set the other one to unlimited (as high as it's settings allow). I would normally choose the limits in the controller, because it will be a faster response cycle as it's all internal to it, the feedback loop is shorter, and it's limits are (should be) able to protect the hardware of the controller while the CA or any other external limiting cannot do that.
If you have both sets of limits in play, it can get complicated to configure a system, and it may be less predictable in behavior under circumstances where both sets of limits interact, or may behave in undesirable ways.
so bike took off like a little motorcycle -at least felt that way- went past a radar with 45km/h

also (moderate) uphill road was good, 25km/h, BUT after only 2-3min @ 25-32A (~1400W) uphill power started to decrease slowly but steadily, down to a mere 3A

what could be d reason? overheating, so fast? Baserunner is rated 30A continuous, 55A peak. couldn't feel it, it's hidden inside frame. motor cold (doesn't have Temp.sensor anyway). battery stable @49V.
after a coffee-break it was back to speedy, but again for only a short time.
any ideas?
If it's only able to do the higher power for a limited time, and then after a sufficient break it is able to do it again, then it is almost certainly temperature limiting inside the controller itself to prevent controller damage.
What kind of temperatures is the BR reaching?
Where and how is it mounted?
Does it have sufficient (or any) airflow?
What kind of heatsinking and cooling do you have on the BR?
Mounted inside the frame, if it's not sufficiently well-connected thermally to the frame, it will overheat from lack of airflow.
On my PRs on the bottom of SB Cruiser, one is mounted to an old thick aluminum L-bracket that was a rack ear mount for some test equipment, and the other is mounted to an even thicker flat aluminum plate with at least as much surface area. boht are in the airflow under the trike, *but* both are also always exposed to the high heat from the road surface, which can reach 150F+ easily here in Phoenix, AZ. Even so, I haven't had a situation yet that caused that to limit current as it takes off from a stop at maximum power just fine even under those conditions (keeping in mind that I only use that power for a few seconds to reach 20MPH, which then only takes a few hundred W from each to maintain when there's no wind).
If it's not the controller doing the limiting, the only other thing in your system that could do it si the Cycle Analyst. If it's limiting, you'll see it on the Diag screen, one button press left of the main screen. There are several leters at the lower left; they should all be lowercase. If any are uppercase, that limit is engaged. You can then investigate your settings to see if the limit is correct or if it needs to be changed to match your hardware, usage, etc.