Hi,
Look forward to needs an -ing verb regardless of it being a state verb or a verb of sensation. We know that these verbs are not usually used in continuous tenses but it doesn't mean that they can't be used as
gerunds. The problem is that we generally think that gerund (like in 'I like
fishing.') and continuous ('I
am fishing.') are the same thing.
Gerunds are half verb / half nouns. You can use state verbs as gerunds like in the sentence,
'Knowing she was there he went to see her.'
Continuous tenses can be recognised because they have the verb be as auxiliary verb (be careful with -ing adjectives.
'I am boring.' is not a continuous sentence. It only means that I am not an interesting person.)
As a conclusion, the
-ing verb after look forward to and any other phrasal verb is not a continuous tense, it's a gerund so, the restriction of verbs of sensation and state verbs doesn't apply here.