"about the same size of the entire game"

unreal 1 200 CD uncompressed, unpatched, is 426mb. and that's without all the unreal gold content.

The reason it's large is because every .u file has to be updated -- you have to recompile them against the new engine version even if unmodified. In this case, all of them to my knowledge are in fact updated compared to previous versions before 227.

There is also around 50~70mb of new textures to support SHIFT_JIS (in theory) as well as additional colors of UWindowFonts, a couple new maps, one which was a bugfix for base coopgame, a new entry level, two new DM maps. the latter maps are to showcase some new 227 features. There is also the supplied "oldweapons.u" mutator, and the installers also include linux binaries which simply inflates the installer if you don't use them.  There is also additional cut content put back in to unrealshare and probably unreali, which increases their filesize further.

all of that plus the required .dlls, sound packages is 162 mb~. the rest is probably the linux binaries, miscellaneous additional translations, some additional settings in ini files, etc etc. not to mention the installer logic itself, which probably isn't small. Hell, even the helpfile fopr UED is 12MBs. 227 also has several new renderers for audio and video.

also really not sure why you're splitting hairs over 200mb in 2020. my cache folder for servers is multiple gigabytes, and a single custom map can be over 30mb not including its required textures etc.

my smallest connected storage media to this computer is 14.5gb, so the 200~mb of patch is approximately 1.32% of that drive which will not break the bank, especially given that most of the content is overwritten data that replaces old data. Really only the extra maps and textures are of any notable size at a glance.

edit: epic's final patch was only a delta patch which required specific patch versions to be installed in order. thats how it could be 7mb. we have to account for all versions to be upgraded, not just a specific one.

Oh, that makes sense. I don't think anyone really did document what specifically the contents are.

you're absolutely right about the doom source ports. there's a ton of unaccounted changes or features, 227 was designed in mind to minimize the changes from the original, while expanding functionality for mods. obviously there are behaviors that were clearly bugs that had to be changed, but I would assume the average player couldn't tell the difference. I'm no longer the average player, so I couldn't tell anymore. The core vanilla gameplay is altered only for bugfixes, for example, an ASMD altfire used to not be able to damage a titan due to how hurtradius works -- the titans collision was so big that the impact actually couldn't overlap the center of the titan.

This was changed to deal damage in that case. Like I mentioned previously -- clearly a bug, but a behavior change nonetheless.