Select the line (or lines) in your OmniGraffle document
Open the Style Inspector (Inspectors Menu ▸ Styles, or ⌘-1)
Select the second style inspector ("Lines and Shapes")
Use the popup menus to choose an arrow style
This problem is caused by Apple's sandboxing of applications (in this case, OmniGraffle). Preview does not receive an entitlement to access the PDF if you just pass it a string to open. From Apple's release notes:
When sending commands to a sandboxed application, such as TextEdit in OS X Mountain Lion, parameters that refer to ...
Option + Double-click
Hold Option/ALT while double-clicking on the line to add a label to it.
If this maneuver instead creates a point to adjust the line from, double-click without Option/ALT. You can swap between Option/ALT-double-click (a) creating a point and (b) creating a label via a setting in Preferences → Drawing Tools → Line Editing.
Also, the ...
It is not currently possible to "Group Canvases" in OmniGraffle Pro 5.
You may email email@example.com and request this as a feature, or visit http://forums.omnigroup.com/forumdisplay.php?f=4 and post this request.
To not change the color, font size and other styling attributes : You must use classes in Text Suite or in Extended Text Suite.
Like this :
tell application "OmniGraffle Professional 4"
set someGraph to solid 1 of canvas 1 of document 1
--set word 1 of text of someGraph to "Hello"
--set characters 1 thru 4 of text of someGraph to "Hello"
There could be quite a few explanations for your delays, and I might start by checking the Activity Monitor and the Console. In the Activity Monitor, are any applications or processes taking up an inordinate percentage of CPU time or RAM? In the Console, are there any errors being reported? These are just basic troubleshooting strategies, and maybe you've ...
Linking to a box or other drawing object is the easy thing to do. It's not a true link to text like you asked, but maybe a small object surrounding the text would be worth the hassle.
Now on to the easy option:
Select any object / shape that exists in the canvas/layers picker (or is visibly selectable).
Select the inspector control if the right inspector ...
With the Line Tool selected you can begin drawing your line and then press the SHIFT key. At this point, with both the mouse button and SHIFT key down, the line will restrict to 45-degree increments.
When dealing with a connection line, where the line's start and end point are linked to an object, it become more difficult. The line's orientation is based on ...
Did you set the margins to 0 under the document inspector?
Edit: never mind this step, you already had it set under Page Setup
Also, make sure to select borderless by going to Paper Handling > select Scale to fit paper size > US Letter Borderless