Hello, this is my first post to the forum and likely the first of many to come. I’m new to CNC and just splurged on a 5Pro 2x4 with 65mm spindle. I’ve assembled everything and was all set to begin my first carve. After going through the procedure in Carbide Motion to load my file and zero the XYZ, I hit the start button but immediately stopped because the spindle moved to begin the carve somewhere in the middle of my stock. For some reason, I expected it to move to the XY zero location before moving to the spot of the first cut. How is the point of first cut determined? Does the machine move directly to this spot after loading the tool and hitting start? Was my panic unwarranted? I shut down because I didn’t want to ruin something like the end mill or a clamp if there was a mistake in my file. Any feedback is much appreciated.
There is no need to move to X-Y zero first, so the machine just heads directly to where it decided to start the first cut.
What @mhotchin said. If you really want to know exactly where the first cut will be, you can see it in the simulation in Carbide Create. Set the playback speed to the minimum, and then play the simulation from the beginning.
Do yourself a favor and ruin a clamp and an endmill. Get it out of the way early so you can see it’s not a big deal 
You can set that point when you select your job setup. In the first image, you can see the job setup cog. Select this and the dialogue box presents you with options. I have entered the size of my work area as 400 x 400mm for X & Y and a thickness of 25mm. I am also measuring the zero height, where the cutter will begin its work at the top of the stock. The highlighted area is the toolpath zero and I have selected center. The smaller highlight shows a red and white quartered circle at the centre of my 400 x 400 area. This is exactly where the tool will measure the workpiece dimensions from and should start at that point, depending on the type of cut. The retract height and the units are important. I have mine set to mm and a retract height of 5mm. that is when the cutter has stopped cutting and must move to another point on the workpiece, it will be raised by 5mm so that it does not cut anything you wish to keep intact. Enter your machine in the drop down menu here too. Material may not make much difference to where you are cutting.
It is your choice as to where you want the workpiece on your overall work area, depending on workholding constraints. Where you place the staring point is also up to you. The next illustration shows a 200 x 200mm square. I have placed the startpoint at the top right of the square and the square at the bottom left of my total available work area. The red and white quartered circle indicates where the cutting work should start from.
The next illustration shows the 200 x 200mm square in the center of the work area. It shows that the start point is also placed at the center of the square.
Finally, if you have an irregular shape, you can still start the cutter in the centre of it. Use the centering tools and then you will find that the cutter will start where you expect it to.
Hope this helps
Thank you for all the help. I was able to run a couple of jobs. I have other questions but will post under Carbide Motion. Thanks again!
LOL. My kind of humor 
Setting up stock parameters and the toolpath zero do not determine where the starting point for a cut are.
Setting the zero is just a reference point and as shown it can be defined as a number of places. (Useful in different scenarios). A file that has the same toolpaths would start its cut in the same place regardless of zero placement.
As others have stated the beginning of the cut will start at some arbitrary spot along the toolpath. (Probably not arbitrary in the coding logic, but it is to us)
@WillAdams has called the starting cut the “Traveling Salesman”. You cannot dictate where the file will start cutting or where on an object it starts. Earlier versions of CC and CM would have the router wander all over the place in cutting objects. The later versions have refined the cutting order to minimize movement but still sometimes wanders around. The only order you can control is which tool path cuts first and that is set by moving the tool paths order. You always want to cut the least invasive tool paths first and cutouts for last. If you cut the cutout first the piece may come loose even with tabs.
the wonders of modern software.
Thank you. I had not explained myself well.
The red and white quartered circle is the reference point for demonstrating the extent of the highlighted toolpath area to be cut within the boundaries of the workpiece. Whether one uses the top of the workpiece or the bottom of the workpiece as the starting point will depend on the work to be completed. I sometimes specify a starting point within the workpiece thickness when carving 3D subjects about which I know the exact thickness dimensions. I do not place the reference point anywhere outside of the highlighted toolpath.
I may use a square endmill cutter with a diameter ranging say… from 3.175 ~ 28mm when removing material. The starting point of the cut will be different for every different size and type of cutter. The reference point… using the example of the centred irregular toolpath illustrated above, notifies the CAD software about the extent of the boundary of the delineated toolpath from that reference point.
It is the user’s choice whether the path is cut as an external or internal profile cut, or even a cut along the centre line, depending on cutter size, type and diameter and whether the user wants to have rounded internal corners or sharp external corners. The cut may follow a raster pattern area clearance or it may be a V carve following along the centre of a line or between two lines and the user may specify that the cut depth should be limited.
When using a specified drilling tool path or any helical toolpath to cut a hole, the location of the reference point has to encompass the X & Y dimensions of the whole workpiece. If it does not, then the hole to be cut will be misplaced on the workpiece because the model dimensions were not determined accurately.
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