Update 17.01.2018: I played around with greebling Jace1969's Executor and various other SSDs floating around the internet but was not able to produce results superior to SeraphsCoal's quickly so I abandoned that and went with brute force hole fixing. Due to inconsistent slicing results, I'm not going to upload those revisions for now. When I have time to play with 3d modeling again, I'll take another whack at fixing the defects of this beautiful model as I know I'll be printing more of them in the future. That said, the model is a completely acceptable non-professional quality print as is, it only takes a little bit of putty or scrap plastic to fix up before painting. On my 19.8% scale model, the only bits that have broken from intermittent handling is the very tips on the nose... so everything's holding up pretty well even with a pound of lead in it. See you again in a year's time!

Update 18.08.2017: Printed whole @ 12% scale with .25mm nozzle and abs+, side edge down with supports and print tabs. Holes printed in model where the internal dowel shafts resulted in the skin being too thin during slicing. Also too thin in front of bridge tower and engine shielding on the bottom of Part 03. Started investigating greebling with 3DS Max and the original Executor model by Jace1969 to fix thin skin and SeraphsCoal's frame defects. Will be a while before ready but I plan to apply techniques to other ships in the future as well.

Update 04.06.2017: Tweaked Lusankya parts
It'd be neat to have emblazons on the ship or stand for the other Executor classes. Like a hammer and a moon on the tail (top rear of part01) for Night Hammer (or more elegant insignia but as SSD's were intended as blatant symbols, eh). Thoughts, ideas, comments?

My list so far (http://www.theforce.net/swtc/ssdlist.html):
Executor
Lusankya (Rechristened in Rebel Starbird colors)
Reaper (Pentastar Alignment)
Intimidator
Brawl aka Iron Fist (gauntlet)
Razor's Kiss
Night Hammer aka Knight Hammer (black stealth hull, hammer and moon)
Terror
Aggressor
Guardian
Vengeance

Update 03.06.2017: Added reinforcement to part 02's engine nacelles.
Added Alliance Starbird insignia to part 03. http://starwars.wikia.com/wiki/Lusankya
I'm printing 3 part with a .25mm nozzle, .1mm layer height, 19.8% scale to fit Prusa i3 mk2. Meshmixer supports. Sliced with Slic3r. Cura had under extrusion on portions of the print. Front and rear thirds (parts 1&2 @ 15hr, 5&6 @ 20hr) printed fine but when I printed the middle (part 3&4 @125hr), pausing @ 113mm to add 540g of size 7 1/2 lead buckshot ballast + pva glue as a fixative, problems appeared.

First, there was a shell separation @ 113mm-113.3mm-ish running 1/2 of the way around and a resonance wave pattern appearing on another 1/4 of the shell from 113mm and up (too much weight? Belts not tight enough? Motor skipping?). There was also a bit of under-extrusion on a portion. The base also started to deform due to additional weight, heated bed and 90 hours of violent printing. To do again, I would print at .15 mm layer hight and print part 3 and 4 separately to add ballast to part 4 just before the top was printed. That or print part 3&4 as a piece, drill out holes in the base, fill with ballast and fill up with pva glue or epoxy. If you don't mess with pausing the print, part 3&4 should print just fine with a 6-8mm skirt.

Fixed Part 01's right edge (from rear view).
Combined parts for a 3 part print.
Combined parts to a whole image for smaller prints.
Remix of a Remix of Jace1969's 275cm Executor.
Overall length @ 100% is 275cm.

To Do: Design snug/snap fit nose guard for manipulation and travel protection. Form fit cardboard box insert? Try to fix excessive greebling of the flat bottom of part 04 (It looks ugly, is easy to manually remove with knife)