1. When creating parts (in my case, borders), you have to draw the part as a "Symbol", then go to Device (where it might or might not be necessary that the new part name match the name of the symbol just defined) and click the "Add" button and add the symbol that you just drew! If you don't do this, when you try to add the part to a schematic, the part is found in the library but it's blank. It's possible to update the symbol later and use the "Update library" function in the schematic tool to pull the changes into the schematic without having to update the "Device" in between.
2. When running the DXF import ULP, you have to be editing a Symbol when you run the ULP and the script that the ULP produces. The ULP simply produces a series of draw commands. It is a good idea to manually fix which layer the drawing is done in (the most recent version of the ULP allows this layer to be chosen ahead of time via dialog).
3. To copy things from one symbol to another, you have to select them as a group, then press the "copy" button while the group is selected. Then you have to close the symbol (can't have more than one up at a time apparently), open the target symbol, then press the "Paste" button to get the copied items attached to your mouse pointer to be set down. A link with the example that helped make this clear:
http://www.bot-thoughts.com/2012/09/eagle-cad-copying-between-schematics.html
4. To manually select items to add to a group rather than using a select border, you need to press control while clicking each item!!! If you accidentally do something that loses the group selection, you can easily get the selection back by pressing the group button again.
5. To do things to a group once the group is selected, you press the button that corresponds to the action (like copy, move, delete, or any of the options under "chanage"), then ctrl-right-click on an item in the group to perform the action on the entire group!!!!!! It is possible to change the size of a bunch of text items in a group with this method if they are all text items.
Here's a link where right-click is explained as important: https://forum.sparkfun.com/viewtopic.php?t=10681
6. To copy a group, such as components and wiring, or a block of text items, select it as a group, then you can right click on the group and get a context menu. None of the context menu items apply to the group except that at the bottom there will be a "Copy: Group" option. You can select that, then close the drawing that you are copying from and open the drawing that you are copying to. This seems to be the sole exception to the pick-an-action-then-ctrl-right-click paradigm described in the previous hint.
Here's a forum thread in which many contributors describe this process: https://forum.sparkfun.com/viewtopic.php?t=2449
7. To create properties for the title block of the border, you add text with the special character '>' in front. Then on the schematic you can create an attribute of the same name for the part to have the value substituted for the word in the part. N.B.: the attribute needs to have display set to 'none' or the value text will show up in both places, in the area of the schematic where the text being substituted is and also as a floating attribute value initially placed next to the handle for the title block. Tom had a lot more familiarity with how it's possible to layer this feature, but for now here is a somewhat funny link in which a bunch of people propose workarounds to avoid using the substitution feature because they don't understand it, and then somebody comments at the bottom thread explaining how it is supposed to work but doesn't get any likes!
http://electronics.stackexchange.com/questions/93773/editing-title-block-frame-in-eagle
