If your download does not begin automatically, click here.
These messages appear because Presto Parts is not an officially "signed" piece of software. Signing costs upward of $700 a year, and Presto Parts does not have the funding to purchase an official certificate. This is an unfortunate side effect of keeping Presto Parts free.
With more funding, Presto Parts may become officially signed in the future. In the meantime, all source code can be verified for safety here.