UnknownShadow200

If you have enabled display scaling in operating system settings, that is not supported yet, so the game will just automatically get scaled up and look blurry.

Better off having an incomplete life than spending the rest of life working on a pointless port

Only zip files with up to 1024 entries are supported, this zip file has 4272 and hence will not load. So you need to delete some of the files in the .zip FYI though, modern minecraft texture packs are quite different from classicube texture packs, so this won't work properly anyways.

What is the error number? And can you please upload or link to the texture pack

Please don't use buggy years old versions of the source code - use the latest version https://github.com/UnknownShadow200/ClassiCube/archive/master.zip

Which part of the instructions is confusing?

You're getting automatically kicked from the server because you turned custom blocks off - because of the way this game is written though, sometimes it won't actually show the kick message.

Are 'allow custom blocks' and 'use CPE' both set to on in Nostalgia Options? Both buttons must be ON, otherwise you won't be able to connect to that server as it heavily depends on using custom blocks.

Are you using a custom compiled libcurl or something? This error here is usually caused by libcurl being compiled without https support. You can get libcurl to output much more debug information if you add _curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); in Http_SetCurlOpts at around line 584 in Http.c

There isn't really a minimum, but having a slower CPU will mean some CPU intensive actions (sending the map, doing lots of physics updates, doing large draw operations) will take longer. Having little memory means you can't make large maps, and you may only be able to have a few levels loaded into memory at the same time. You just need to install mono framework (ubuntu, apt-get install mono-complete). Then in Terminal, type either mono MCGalaxyCLI.exe (for command line) or mono MCGalaxy.exe (for GUI)

Does clicking on Delete button to change mode to Place not work? What happens when you try to edit settings?

Some ISPs/routers do not allow connecting to your own external/public IP address. When you join from the server list, the game simply connects to the server's IP address. Hence you cannot connect to your own server, since the server's IP address is the same as your own public IP. When you join from the website, it additionally checks if your IP address is the same as the server's IP address. If it is, then the website automatically configures the game to connect to 127.0.0.1 instead.

What issue do you have when you try running a server? Most server software requires .NET 4.0 to be installed, which is available for Windows XP and later.

Always has.

[game folder]\texpacks for desktop client. Out of luck for web client.