Ever since I've updated this modpack to v6, I have been unable to enter the nether. The flint and Steel does not light up the portal. It doesn't cause a crash, but it just doesn't light up and it wastes a use of the flint and steel. Removing access to the nether make using Metallurgy completely pointless since all the nether metals there have some sort of use.
I would assume a quick fix for this would be to download Alz454's Enhanced Portal Mod (this link directs to the MC Forum topic), until there's a fix for it.
Also, I'm not exactly sure if this was the right area to post this, if it is, I sincerely apologise.