"Plan" makes me think of building/construction plans, even you describe it as a new "estimating" tool, so why not estimatelike.pro? (or any alternative that more closely connects the tool to the concept of "estimating").
For any given problem, I always think that the model (or "business logic") comes first, and then the GUI. I have no idea from you website what's the underlying model for your tool.
From browsing the home page it makes me think it this tool works kind of like "a frontend for a spreadsheet" ... but I'm just using my imagination, since you don't explain how it works or what it looks like.
Hope this doesn't sound too negative. Congrats on launching!
P.S.: the slideshow has to be the most cryptic I've seen in a long time... I can see tiny lil arrows left and right that are hard to click, next to "mysterious" integers that change every time I click the arrows. I'm guessing it may describe how many slides are to the left and right? Why not using the "de facto std" of showing one dot per slide, and highlight the current one?
Addendum 2: My preference would be a DSL to describe this kinds of problems, rather than a drag-and-drop, GUI interface. Advanced users could do away with the mouse completely, or even run the models from the command line or embedded in another app. Any given "fixed GUI" will always have limitations, but if you want to make it easier for non-power-users, you can also build a simple GUI on top of the DSL.