How tight is tight when adjusting your blade? My blade bends when cutting curves. Thank you

This is probably because the offsetting tapered discs in the dado are not lined up to compliment each other and your dado is tipping more to one side than the other - if the blade was tipping to the left and right the same amount, both sides would cut to the same depth and the deepest part would be right in the middle. In an extreme case, if the blade tipped only to the right and not to the left, then the left side would cut the deepest and the bottom of the cut would curve up (shallower) to the right.
The same effect could be due to your arbor not being set exactly at 0 or 90 degrees. The angle indicator on the saw is usually not very accurate. Put a regular blade in, raise it up all of the way, then check for squareness between the table and the side of the blade (using a known good square). Adjust the tilt until you are good, then put the adjustable dado back in.
Good luck!

THE BLADE IS BEND CHANGE IT

Unfortunately that is just to thick of material to cut with a jig saw blade. Plywood is made up of several layers and your blade is trying to follow the grain on one of them. You can try a metal blade and high motor speed low travel rate, but it will quickly heat up the blade and warp it making your problem worse if you don't stop often. If you are trying to make straight and curved cuts, I have the best luck with a rotary cutter such as the roto zip, but plywood easily snaps the bits.

just jack it up so you can get under the deck and unscrew the bolt on center of ech blade take note on how the curves of blade are angled do one at a time incase you forget but bolt back up tight and you are ready to cut if you try to resharpen the blades make sure you balance them or they will mess up the deck bearings

On the aduster screw where you tighten blade ... is there an extra nut? I think you need to screw that nut tight so the adjuster screw cannot rotate from vibration.

before adjusting spring pressure check the two screws either side of the hinge *** make sure they are tight and also check to see if this component has pulled away from the body.

It sounds like you got the cable to tight. The brake cable applys the brake to the pulley to help stop the blades when PTO is disengaged. With it being tight it might be applying the brake and that is the reason your blades are not running at full speed. If you keep using it that way it will wear out your brake and possibly damage a pulley. I suggest you loosen the brake cable or replace it with a new one.

check belts are tight and not slipping

The 1590, like several Bosch jigsaws, has a selector switch to choose the type of cutting action. You have to choose the appropriate cutting action, either straight or oscillating, to accommodate the material you cut and the blade you cut with. For instance, if using a very slender blade for clean curved cuts in wood, a slight oscillating motion ( setting II or III) reduces friction on the blade. 
If you choose the straight cutting action you get maximum accuracy, but drastically increase the friction because the blade is held firmly to the roller bearing.  A slender blade can handle that for brief periods, (say... less than thirty seconds) in soft, thin wood with a straight cut. In hard woods or engineered wood products ( plywood, MDF etc.) the thin blade will heat up and bend. 
You can reduce friction by choosing an oscillating cutting motion, or you can use a larger, sturdier blade. The "Aggressor" blades do not cut as smoothly as the "clean" blades, but they cut faster and are stronger. To cut thick wood ( 4x4 ) or a long cut in engineered material, that is the blade I use. Select number III or number II for 'type-of-cut' and use a bigger blade. See if that stops the "bucking."
Good luck!

Blade Width is important when purchasing a band saw. Most saws accept narrow 1/8" blades for cutting detailed designs and tight curves. Better saws also accept wider blades. Wide blades don’t flex as much as narrow ones, but they make accurate straight cuts in thick stock quicker. There are also some wide blades available that can cut metal.