I'm a developer who's trying to get the hang of Blend. I've always used Blend to mess with control templates and such, but I'm trying to get the hang of using it for basic UI design, since I figure it's probably a bit faster than typing the XAML up manually in Visual Studio.
Right now I'm just trying to create a basic Grid, but I'm seeing two default behaviors that I'm hoping someone can show me how to change.
1) When I hover my mouse outside of the design surface, I see the temporary yellow line to show up, where the new Grid Column / Row will be when I click. The problem is that the newly created rows are set to heights like 0.2297* How do I get Blend to attach regular heights, like 250?
2) Ignoring 1), once I have some rows and columns, when I drag a button, or combo box, etc, onto one of the cells, it drops it exactly where I release the mouse, while adding some large margins to position it there. Is it possible to tell blend to just drop the control into the cell, and leave the margins alone?
Grids are awesome but it takes a bit of play to get proficient at working with them in Blend. Here are some tips to get you started (I cover this in detail in chapter 4 of my book).
1) When you use the snap lines to create rows and columns Blend automatically makes them relative (Star) sized, which is the behavior you are seeing. To change the row/column style to fixed (Pixel) sizes, click on the Padlock icons to the left and top of the desired rows and columns. Then, either edit the values in XAML or you can click near (but not on) the padlock to select the row or column. This will open the sizing properties in the Properties panel.
2) The short answer is "No". Blend will always add Margins when you draw the element in a cell unless you take care to draw them to the borders. This is too difficult and time consuming, so I just make sure I draw it somewhere inside my target cell. Now I can right-click the element and select "Auto Size > Fill" and the element will fill up the cell: no Margins, Width and Height set to Auto, and Horizontal and Vertical Alignments set to Stretch. [FWIW, addressing this is my number one feature request for Blend.]
I hope this helps.