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Hello and welcome!
Yes, the terrain profiles are drawn such that the transmitter is on the left and your house is on the right. The terrain between the transmitter and your house is shown in gray. The colored areas above the terrain show the approximate signal strengths in the air passing over the terrain. The vertical dimensions have been exaggerated to make some of the smaller terrain features more visible.
The ground elevation at your house and at the transmitter are already taken into account. You do not need to do anything to compensate for a high ground elevation. The Earth's curvature is also automatically factored into the model.
Note that the scale of the profile plot is several miles in the horizontal direction (your distance to the transmitter, 53 miles is about 280,000 feet). Even though the vertical scale of the profile is exaggerated, the vertical dimension of the image still represents several hundred or even a few thousand feet. If you specify your antenna height as 10, 30, or even 100 feet, it is probably going to be barely noticeable on the profile view. Even a 100 foot tower will be infinitesimal when compared to the mountains and foothills that can get in the way of your signals.
The terrain data is primarily derived from the Shuttle Radar Topography Mission (SRTM) data that was collected in the year 2000. In most cases, the terrain data is accurate to 90 meter "bins" or better. The model does not take into account buildings, trees, or other localized obstructions.
Even if you get "1Edge" diffraction of your signals, it's still possible to get plenty of signal for your receiver. There are some parts of the country where the majority of the people get their signal via "1Edge" or "2Edge" diffraction because there are lots of rolling hills in the way.
The curvature of the Earth can also be a source of blockage. For most stations, the line-of-sight horizon is usually somewhere around 50 to 70 miles away from the transmitter (depends on the ground elevation and tower height of the transmitter relative to the surrounding terrain). At 53 miles, you would be getting close to the optical horizon of a "bare Earth", so even a small hill or terrain bump may be enough to get in the way and cause your situation to show "1Edge" diffraction.
Bottom line is that the Noise Margin (NM) column is what really matters. The Path type may be interesting to know, but usually doesn't make any difference as long as you have enough antenna to pull in the signal.
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