LONDON—The London Metal Exchange had hoped to get the global market for nickel motoring again on Wednesday after a week in limbo. It didn’t work out as planned. The world’s oldest metals exchange was forced to halt trading on its electronic system within a minute of opening due to a technical glitch and when it resumed in the afternoon there were very few trades. The shambolic reopening piled more pressure on the LME, which is already facing a hail of criticism for suspending the market after a wild spike in prices last week left some traders facing billions of dollars in losses. LME nickel prices are used as a reference for deals between end users of the metal and producers, and the disorderly market resumption left some traders questioning whether participants might look for alternative venues. “This is difficult for the market and all its participants,” said Michael Widmer, head …