Shortcuts List

General (System Wide)

Ctrl + V Paste Mode
Ctrl + Shift + A Action Mode

Paste Mode

Ctrl + V is used to enter the [Paste Mode] (see also here).
As releasing both keys inserts the current displayed clip, the key sequence enters the intrinsic [Paste Mode]. While being in Paste Mode (Ctrl pressed) a few more actions can be performed by pressing keys:
V - Move forward through Multiple Clipboards (from 1 to 2 , 2 to 3, …)
C - Move backward through Multiple Clipboards (from 3 to 2 , 2 to 1, …)
S - Add current Clip to Windows Clipboard
X - Toggle between Cancel, Delete, Copy, Move and Delete All MODE 
E - Export current clip
A - Jump to first clip
F - Activate Search / Entering [Search-Paste Mode]
H - Edit Clip
Z - Toggle pasting formats
T - Add tags to clips
Q - Move clip to first position
 (i.e. Enter) - Start Multiple Pasting Session
Space - Fix/un-fix a clipboard at its position (Fixate)
 (i.e. Up) - Change channel to 1 up (+1)
 (i.e. Down) - Change channel to 1 down (-1)
1..9 - Move to clip {num} ahead/behind of current clip
Shift - Hold Shift with Ctrl to delete clip after pasting. See Paste Popping
F1 - View listing of all keys in Paste Mode
See this ClipjumpCustom.ini example to change these keys

Search in Paste Mode (Search-Paste Mode)

The following key sequence enters [Search-Paste Mode] while being in [Paste Mode] (see also here): Now you are in [Search-Paste Mode] and several commands are available via keypress:
Enter - Paste
Home / Esc - Cancel
 (i.e. Up) - Move one clip up (+1)
 (i.e. Down) - Move one clip down (-1)
Ctrl+[Paste Mode] key - execute a [Paste Mode] feature when [Search-Paste Mode] is active
Ctrl + Enter - [Multipaste Mode] within [Search-Paste Mode]- Paste without closing the [Search-Paste Mode] (releasing Ctrl does NOT cancel the [Search-Paste Mode] here)
Ctrl + F, then release F - Switch back to [Paste Mode]
See ClipjumpCustom.ini to change these keys

Cancel, Delete, Copy, Move and Delete All Mode

While being in Paste Mode, pressing X repeatedly toggles between several modes:
X - [Cancel Mode] - cancel the current paste operation
X - X - [Delete Mode] - delete current clip
X - X - X - [Move Mode] - Move clip to a different channel
X - X - X - X - [Copy Mode] - copy clip to a different channel
X - X - X - X - X - [Delete All Mode] - deletes all clips
Note that [Cancel Mode], [Delete Mode], [Move Mode], [Copy Mode] and [Delete All Mode] are inter-related. The program cycles through these modes when you press X while holding Ctrl.
So, pressing X while holding Ctrl in [Delete All Mode] will switch back to [Cancel Mode].

Action Mode

Ctrl + Shift + A is used to enter the [Action Mode] (see also here). A dialog box pops up, offering a lot more "actions" which can be performed. These actions can be accessed via keypress:
B - Hold Clip
C - Copy File path(s)
D - Disable Clipjump
E - Settings
F - Copy File Data
F1 - Help
F2 - Paste Mode Shortcuts
H - Clipboard History
L - Ignore Windows Manager
M - Plugin Manager
0 - Channel Organizer
P - PitSwap
T - One Time Stop
U - Sync Clipjump Clipboard
X - Copy active folder path
Esc - Exit Action Mode Window

0..9 - Activate channel whose ID (number) is pressed
The hotkey for [Action Mode] can be user defined. (see: ClipjumpCustom and Settings Editor to change this key)
To change Action Mode easy keys, see Changing Action mode keys