I think I have the first sentence, but I'm including it for context. I have most of the second sentence. I may not have worded the translation quite well, though, and I've highlighted the questionable parts.
Hanc protestationem meam non sine causa toti huic operi nostro praeposui, propterea quod noverim plures esse futuros: qui cum ea, quae scripsimus, intelligere nequeant, ad iniurias conversi, bona & sancta studia nostra malis artibus aut superstitiosis adinventionibus sint concessuri.
His, cum futuri sint, & omnibus haec nostra synthemata sunt lecturi, attente supplicamus, ut si hanc secretam traditionem nostram intellexerint, perpetuo fervent occultam, nec mysteria tam miranda transfundant in publicum.
I have put this, my declaration, in front of this, our complete work, not without reason, because I may learn that there will be more: anyone, when they may not be able to understand what I have written, turning towards injury, might be ready to consign our good & holy study to evil science or superstitious inventions.
To these, seeing that they might exist, and to anyone whatsoever reading this, our synthesis, we beg you to pay attention, so that if they understand this, our secret tradition, they will continually be busy with the secret, and they should not transfer? pour out? the mysteries to be so marvelled at in public.