I vaguely remember that the local aeroclub has a reputation for being helpful to visitors, they seem to get quite a deal of G/A transit traffic. I would certainly recommend getting in touch with them before flying.
Needless to say, perhaps, but do think of carrying vacciniation certificates.
As for the radio: yes, in French only, but it is mentioned as A/A (air to air) meaning there is no promise you will get any reply to your calls.
PS why don't you go for EBSH Saint Hubert? Don't like grass runways, perhaps?