I places the verb tense sequences in te Englih make pure nonsense. Maybe some punctuation would clarify things a bit - if all the sentences were very short we would probably not have any tense conficts within a sentence - but listening to the singer doesnt seem to me to suggest any punctuation.
Trying to stick to the apparent meaning (AKA the ungrammatcal mess) of the English lyrics as presented requires an equally messy set of grammatical errors in French. In the last stanza for example I had great difficulty in refraining from replacing every "irai" by "irais"; but that would have made it a bad translation because a good translation of something wildly ungrammatical should surely reflct that wild ungrammaticality - it would be cheating to make sense in the French when the original English doesn't make sense.
Sadly this is likely to bother far more French speakers than the same errors in the English will bother English people.