Hi,
I tried with the nightly build and it works like a charm. Driver supports both DMFC and FocusCube (tested)
Can you check if you have the correct version?

$ dpkg -l |grep -i libindi
ii libindi-data 1.7.4~201809071124~ubuntu16.04.1 all Instrument-Neutral Device Interface library -- shared data
ii libindi1:amd64 1.7.4~201809071124~ubuntu16.04.1 amd64 Instrument-Neutral Device Interface library -- shared library

$ dpkg -l |grep -i kstars
ii indi-qhy 1.8~201809081102~ubuntu16.04.1 amd64 INDI QHY Driver. This driver is compatible with any INDI client such as KStars or Xephem.
ii kstars-bleeding 6:2.9.8+201809070838~ubuntu16.04.1 amd64 desktop planetarium for KDE
ii kstars-bleeding-data 6:2.9.8+201809070838~ubuntu16.04.1 all data files for KStars desktop planetarium
ii kstars-bleeding-dbg 6:2.9.8+201809070838~ubuntu16.04.1 amd64 debug information for the desktop planetarium for KDE

Logs from INDI Control panel:

---

2018-09-08T17:29:20: [INFO] Focuser is moving to position 200
2018-09-08T17:29:19: [INFO] Focuser reached requested position.
2018-09-08T17:29:18: [INFO] Focuser is moving to position 100
2018-09-08T17:28:58: [INFO] Device configuration applied.
2018-09-08T17:28:58: [INFO] Loading device configuration...
2018-09-08T17:28:57: [INFO] Pegasus DMFC is online.
2018-09-08T17:28:57: [INFO] DMFC is online. Getting focus parameters...
2018-09-08T17:28:57: [INFO] Auo search is disabled.
2018-09-08T17:28:57: [INFO] Debug is enabled.
2018-09-08T17:29:22: [INFO] Focuser reached requested position.

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