Does version 1.86 help in any way?
No. Sins of a Solar Empire: Rebellion v1.86 is completely broken for me, just as v1.84 was.
Version 1.86 initially failed to install because I still had v1.83 installed, and the GOG patches are not universal updaters. I renamed my player profile directory and started v1.83 to create a clean profile. I got the initial movie, which my personal settings normally do not show, so I think the game recreated the profile as intended. Next, I downloaded the v1.84 and v1.85 patches, then installed v1.84, v1.85, and v1.86 in series, taking care not to start the game until v1.86 was installed. Thus, with this profile, the game has only been started with v1.83 and v1.86, but not with v1.84 or v1.85. I mention this in case it is useful to know that I did not wipe the system and install directly from v1.86.
v1.86 still crashes on startup in my no-network environment. The addresses are different, but all the symptoms are the same as I remember. The game blacks the screen, then pops up a Windows message box reporting an error and another reporting the path to the minidump. The minidump is tiny: 96kb.
CS:0023 SS:002b DS:002b ES:002b FS:0063 GS:006b
EIP:00433f06 ESP:0033fc74 EBP:0033fcdc EFLAGS:00210202( R- -- I - - - )
EAX:00000000 EBX:00000000 ECX:007f9e24 EDX:00000000
=>0 0x00433f06 in sins (+0x33f06) (0x0033fcdc)
1 0x004059fa in sins (+0x59f9) (0x0033fda0)
2 0x00685a4c in sins (+0x285a4b) (0x0033fe30)
I then removed my profile directory entirely, in case the game was confused by stale profile preferences. I started v1.86 again and it again crashed on startup, with the same symptoms and same register/backtrace context. The game recreated a few profile files and directories before crashing:
My Games\Ironclad Games\Sins of a Solar Empire Rebellion\
My Games\Ironclad Games\Sins of a Solar Empire Rebellion\Mods-Rebellion v1.83\
My Games\Ironclad Games\Sins of a Solar Empire Rebellion\Mods-Rebellion v1.83\EnabledMods.txt
My Games\Ironclad Games\Sins of a Solar Empire Rebellion\Setting\
My Games\Ironclad Games\Sins of a Solar Empire Rebellion\Setting\rebellion.user.setting
Yes, it created Mods-Rebellion v1.83 even though it is supposed to be v1.86. Perhaps this was an intentional choice to maintain compatibility with older versions.
f48b62c953f840d850f3c263c8822208cc3c3fac patch_sins_of_a_solar_empire_rebellion_ultimate_184.108.40.206.exe [v1.83 -> v1.84]
fc8d44abf76aab8297be6223d8a480f0f2eca95e patch_sins_of_a_solar_empire_rebellion_ultimate_220.127.116.11.exe [v1.84 -> v1.85]
6114134ac4b7c81876a3cdaa3b53026e9fb9f9c7 patch_sins_of_a_solar_empire_rebellion_ultimate_18.104.22.168.exe [v1.85 -> v1.86]
b6fde16f701401d7db926f2a5b54adc5e1148fab Sins of a Solar Empire Rebellion.exe
As with the other poster, I noticed that the path used for the minidump claims to be v1.85, not v1.86.