Download Play services are not used by the Download Play child application at all(the title which runs on the Download Play clients). This is used instead: APT:GetWirelessRebootInfo.

There can only be one session open for each individual DLP service at a time.

Download Play Client Service "dlp:CLNT"

Command Header Available since system version Description
0x000100C3 ? ?
0x00020000 ? ?
0x00030000 ? Unknown. Writes 0x18-bytes of output starting at cmdreply[2].
0x00040000 ? Unknown. Writes an output u16 to cmdreply[2].
0x00050180 ? ?
0x00060000 ? ?
0x0007.... ? ?
0x0008.... ? ?
0x0009.... ? ?
0x000A.... ? ?
0x000B.... ? ?
0x000C.... ? ?
0x000D.... ? ?
0x000E.... ? ?
0x000F.... ? ?
0x0010.... ? ?
0x00110000 ? Writes 9-bytes of output starting at cmdreply[2].
0x0012.... ? ?
0x0013.... ? ?
0x0014.... ? ?

Download Play Server Service "dlp:SRVR"

Command Header Available since system version Description
0x00010183 Initialize...
0x00020000 Finalize...
0x00030000 unknown...
0x00040000 unknown...
0x00050080 unknown...
0x00060000 unknown...
0x00070000 unknown...
0x000800C0 unknown...
0x00090040 unknown...
0x000A0040 unknown...
0x000B0042 unknown...
0x000C0040 unknown...
0x000D0040 unknown...
0x000E0040 unknown...
0x000F0303 unknown...
0x00100000 unknown...

"dlp:FKCL"

Command Header Available since system version Description
0x0001.... ? ?
0x0002.... ? ?
0x0003.... ? ?
0x0004.... ? ?
0x0005.... ? ?
0x0006.... ? ?
0x0007.... ? ?
0x0008.... ? ?
0x0009.... ? ?
0x000A.... ? ?
0x000B.... ? ?
0x000C.... ? ?
0x000D.... ? ?
0x000E.... ? ?
0x000F.... ? ?
0x0010.... ? ?
0x0011.... ? ?