I'll try, thank you very much for your hints.
By the way, I've written to the Option support asking for some advice and they replied
The 3G device you have purchased is an OEM product. We are sorry that we are not able to assist you with your support inquiries. The product has been
commercialized and is supported by your local supplier. Please contact your
local supplier-support helpdesk. (i.e. Asus)
They built this blasted modem, they know even the smallest detail of it but they don't give me any support because I have purchased it as an OEM product????? I don't give a hang about it being an OEM or what else, it's an Option product and Option MUST support me. This is not about being honest with customers...
I swear next time I'll be much more careful about what is inside a PC. And I don't want to get in touch with any other Option product, whether OEM or not.