I've updated to 10.11.14 and this didn't have any effect. As suggested, I've also downloaded etrecheck and this is the report:
EtreCheck version: 2.9.11 (264)
Report generated 2016-04-27 09:40:23
Download EtreCheck from https://etrecheck.com
Runtime 1:44
Performance: Excellent
Click the [Support] links for help with non-Apple products.
Click the [Details] links for more information about that line.
Problem: Apps are crashing
Description:
Hallmark card studio
Hardware Information: ⓘ
iMac (Retina 4K, 21.5-inch, Late 2015)
[Technical Specifications] - [User Guide] - [Warranty & Service]
iMac - model: iMac16,2
1 3.1 GHz Intel Core i5 CPU: 4-core
8 GB RAM Not upgradeable
BANK 0/DIMM0
4 GB DDR3 1867 MHz ok
BANK 1/DIMM0
4 GB DDR3 1867 MHz ok
Bluetooth: Good - Handoff/Airdrop2 supported
Wireless: en1: 802.11 a/b/g/n/ac
Video Information: ⓘ
Intel Iris Pro Graphics 6200
iMac 4096 x 2304
System Software: ⓘ
OS X El Capitan 10.11.4 (15E65) - Time since boot: about 2 days
Disk Information: ⓘ
APPLE HDD HTS541010A9E662 disk0 : (1 TB) (Rotational)
EFI (disk0s1) <not mounted> : 210 MB
Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB
Macintosh HD (disk1) / : 998.98 GB (932.95 GB free)
Core Storage: disk0s2 999.35 GB Online
USB Information: ⓘ
Broadcom Corp. Bluetooth USB Host Controller
Apple Inc. FaceTime HD Camera (Built-in)
Thunderbolt Information: ⓘ
Apple Inc. thunderbolt_bus
Gatekeeper: ⓘ
Mac App Store and identified developers
System Launch Agents: ⓘ
[not loaded] 6 Apple tasks
[loaded] 149 Apple tasks
[running] 83 Apple tasks
System Launch Daemons: ⓘ
[not loaded] 47 Apple tasks
[loaded] 146 Apple tasks
[running] 95 Apple tasks
User Launch Agents: ⓘ
[running] com.amazon.music.plist (2016-02-13) [Support]
User Login Items: ⓘ
iTunesHelper Application (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)
Other Apps: ⓘ
[loaded] 397 Apple tasks
[running] 208 Apple tasks
Internet Plug-ins: ⓘ
Default Browser: 601 - SDK 10.11 (2016-04-25)
QuickTime Plugin: 7.7.3 (2016-04-25)
3rd Party Preference Panes: ⓘ
None
Time Machine: ⓘ
Time Machine not configured!
Top Processes by CPU: ⓘ
38% mds
22% mdworker(14)
2% WindowServer
1% kernel_task
1% fontd
Top Processes by Memory: ⓘ
857 MB kernel_task
467 MB softwareupdated
254 MB Mail
238 MB mdworker(14)
221 MB com.apple.WebKit.WebContent(3)
Virtual Memory Information: ⓘ
460 MB Free RAM
7.55 GB Used RAM (2.56 GB Cached)
0 B Swap Used
Diagnostics Information: ⓘ
Apr 27, 2016, 09:32:23 AM ~/Library/Logs/DiagnosticReports/Hallmark Card Studio 2016_2016-04-27-093223_[redacted].crash
com.hallmarksoftware.hallmarkcardstudio - /Applications/Hallmark Card Studio 2016.app/Contents/MacOS/Hallmark Card Studio 2016
Apr 25, 2016, 12:21:31 AM ~/Library/Logs/DiagnosticReports/Hallmark Card Studio 2016_2016-04-25-002131_[redacted].crash
Apr 25, 2016, 12:08:29 AM Self test - passed
Apr 24, 2016, 11:50:36 PM ~/Library/Logs/DiagnosticReports/Hallmark Card Studio 2016_2016-04-24-235036_[redacted].crash
I've only had the mac for a short while and am still learning, but I have limited knowledge of the tech stuff, so any help would be welcome.