In generator dispatch strategy, I am wondereing have i made a correct decision chosing cycle following and a set-point of 80%?  (Is it possible to tick both load folowing a nd cycle charging at the same time. Is it possible or advisable?)

It's both possible and advisable to check both cycle charging and load following.  It just means HOMER will try one, then the other, and see which is best.  I didn't think of that when I reviewed your file, but it's a good idea.

Load following tends to be better in systems (big or small) with high renewable penetration, but it's hard to guess a priori which is better.  It's easy to let HOMER try them both and tell you which is better.

The 80% setpoint is fine.  Without the setpoint, HOMER often cycles the battery bank in shallow cycles at low states of charge.  That kind of charge-discharge regime is hard on lead-acid batteries in real life because at low states of charge sulfation can happen, which kills the batteries prematurely.  HOMER doesn't know anything about sulphation so without the setpoint it is happy to let the batteries languish at low states of charge for long periods.  The setpoint state of charge is a common feature in real systems, and 80% is a realistic number.