"qaSpa' lot maQuch."
Translation:Before the catastrophe we were happy.
Nothing wrong with your English version. In both English and Klingon you have the option of putting the dependent clause first or the main clause first. Since you have the same options in both languages, you should keep the order the same in both languages.
Most of the time the order won't really matter, but sometimes the clauses are put in a particular order for a particular effect. The Klingon first talks about the catastrophe happening and then about happiness. The English translation should also talk first about the catastrophe happening, then about happiness.