Cloudy

Update to 511. It fixes the bug introduced in 510.

It is a launcher issue - take it up with the technic guys.

There is a fix - fixing your ID's! Redpower just isn't graceful at handling ID conflicts right now.

Optifine is broken with forges above 499 right now. Try seeing if your HD texture pack works without Optifine, until the maker fixes it.

Forge includes some HD patches. Most HD texture packs will work. If not, just uninstall Optifine until the maker fixes it, and go back to vanilla pack.

Are you using MCPatcher? If so, there's your problem - don't use it!

Tekkit uses a build of bukkit with integrated forge - but it is not an official forge build nor an official bukkit build hence why neither can help you. Failing Tekkit forums, try MCPortCentral forums.

This is also the wrong place. Try tekkit forums.

Have patience. This is a forum - people will reply if they know something.

Except there's no way that the mod on the client can affect the server tps. It has no control over the server logic.

What would tell the server which mods it has joined with? The client. You see the issue there? A client could just lie about which mods it has installed - and you'd be back to square one.

No, it is on the forge files website - branches are at the bottom. Have you tried without MultiMC? This isn't fully tested yet, so it is no surprise there will be issues.

I have actually seen this issue before recently. The problem is the quotation marks around %s in fml.py - on some systems it doubles them. No idea why, but removing the quotation marks should work.

Logs would be helpful - server and client.

You say it doesn't work after removing it from mods folder. Do you have a new log after that?

Editing base classes is hardly a solution. The simple solution is, change Block.blocksList[] and set the gold and iron vanilla ores to null first.

Change width in GuiButton to be public - it's a bug with Octo Bearded Nemesis. You obviously don't need to release that modified class.

Forge includes built in HD texturepack support.

New log after deleting META-INF?

You should see a log file in your .minecraft folder called ForgeModLoader-client-0.log. Please post a pastebin link to it here.

While that may be true, Modloader is less picky when it comes to those things - so perhaps FML should sort it out for Modloader mods which try to do that (if possible). Are you just using Modloader functions?

The MCPC build is not supported by the forge team. You will have to take it up with the author of the MCPC build.

You're out of luck for 1.4.2 basically - Lex fixed it in the next version, which is a 1.4.4 version.

Try here: http://files.minecraftforge.net/

Tekkit issue, take it up with them.