Also, your question implies that you think that https is the cause of the slowness.  Does that mean that you were seeing better performance over http and that the only change you made was adding the ssl certificate?

Yes

The only slowdown SSL could cause in a properly-configured environment would be due to certificate validation (OCSP), and this would take place just when the connection is established and so it wouldn't account for general slowness.

The channel encryption is handled entirely by the browser at one end and IIS at the other without the involvement of any Laserfiche software, so you don't have to limit your queries to our forums.