The load time for a K2 SharePoint WebPart is significantly longer the first time that the WebPart is loaded than for subsequent loads. This causes a significant delay when opening a K2 Process Portal page for the first time.
K2 SharePoint WebParts will load asynchronously instead of synchronously. This will allow the page to load while the WebParts are still loading.
This issue has been resolved in the latest K2 release.