That’s indeed a known effect of the “Ad Blockers” on any browser they prevent the pixel from loading and the pixel helper from functioning properly. We do recommend that you disable the ads blocker on your pages to see the events being recorded.
As for the events not being fired when someone buys, I believe it could be because they never landed on the next page (eg. next OTO or Thank you page). PayPal (by default) shows an intermediary page after each purchase with a summary of the purchase and a “Return to merchant” button, which your customers have to click to get redirected back to the next step.
There is however an easy way to fix that, Simply follow this short tutorial: 1 Click Upsell Hack For Paypal Plugin On Clickfunnels, to remove that “return to merchant” step. You only need to follow that step only once on your “recipient” PayPal account.
Hope that helps, do let us know how it goes,