well, the pictures and videos of the M777s howitzers while being loaded onto the planes for transport, and the first ones that have been published of their use, show that those delivered are the basic version, without the ballistic computer, so basically, paper and pencil. and I think I have read that the barrel is the light model, which suffers more wear and tear and less shoots with longer range munition.
As for the accuracy of the shells, who knows if they were issued M982s and/or M1156 PGKs (these use GPS). Although Ukraine has (or had?) a type of laser-guided ammunition before the war. the Russians have the laser-guided Krasnopol shell and some similar heavy mortar shells. The issue is that the GPS can be jammed/spoofed, and the laser blocked/disrupted and/or the emitter destroyed.
About the range, unless they have M982 shells in some improved version (40km), the maximum range is about the same than the Russian artillery, 25-30km. If the Russians deploy their modernized self-propelled artillery, their range is over 40 km (maybe even 80 km, depending on the projectile)