Here is the echo I get when printing (ack is enabled):
11:13:39.685 : X:0.00 Y:0.00 Z:250.00 E:0.00 Count X:24484 Y:24484 Z:24484
11:13:39.685 : ok
11:13:39.685 : echo:N14 G1 Z15 F053
11:13:39.685 : ok
11:13:39.685 : echo:N15 M107*17
11:13:39.685 : N22 M117 ETE -55s30
11:13:39.685 : ok
11:13:39.685 : N23 G92 E0*118
11:13:39.685 : echo:N16 G9039
11:13:39.685 : ok
11:13:39.685 : echo:N17 M82*47
11:13:39.685 : ok
11:13:39.685 : N24 G1 Z-140.8 F600010
11:13:39.685 : echo:N18 G92 E0*126
11:13:39.700 : X:0.00 Y:0.00 Z:15.00 E:0.00 Count X:24481 Y:24481 Z:24481
11:13:39.700 : ok
11:13:39.700 : echo:N19 G2134
11:13:39.700 : N25 G1 E-2 F2400*5
11:13:39.700 : ok
11:13:39.700 : echo:N20 G9034
11:13:39.700 : ok
11:13:39.700 : N26 G92 E0*115
11:13:39.700 : echo:N21 M8242
11:13:39.700 : ok
11:13:39.700 : echo:N22 M117 ETE -55s*30
11:13:39.700 : ok
11:13:39.700 : echo:N23 G92 E0118
11:13:39.700 : N27 G1 X53.414 Y-20.504 F6000*85
11:13:39.700 : X:0.00 Y:0.00 Z:15.00 E:0.00 Count X:24477 Y:24477 Z:24477
11:13:39.700 : ok
11:13:39.700 : N28 G1 E2 F240037
11:13:39.700 : echo:N24 G1 Z-140.8 F6000*10
11:13:39.700 : ok
11:13:39.700 : echo:N25 G1 E-2 F24005
11:13:39.700 : N29 M204 S200*95
11:13:39.716 : ok
11:13:39.716 : echo:N26 G92 E0*115
11:13:39.716 : X:0.00 Y:0.00 Z:0.00 E:0.00 Count X:24471 Y:24471 Z:24471
11:13:39.716 : ok
11:13:39.716 : N30 G1 X54.352 Y-18.061 E2.56986 F3000*20
11:13:39.716 : echo:N27 G1 X53.414 Y-20.504 F6000*85
11:13:41.732 : echo:busy: processing
11:13:43.748 : echo:busy: processing
11:13:45.760 : echo:busy: processing
11:13:47.776 : echo:busy: processing
11:13:49.776 : echo:busy: processing
11:13:51.792 : echo:busy: processing
11:13:53.808 : echo:busy: processing
11:13:55.826 : echo:busy: processing
11:13:57.842 : echo:busy: processing
11:13:59.858 : echo:busy: processing
11:14:01.876 : echo:busy: processing
11:14:03.888 : echo:busy: processing
11:14:05.897 : echo:busy: processing
11:14:07.911 : echo:busy: processing
11:14:09.442 : ok
11:14:09.442 : echo:N28 G1 E2 F2400*37
11:14:09.442 : N31 M117 ETE -55s*28
11:14:09.442 : ok
11:14:09.442 : echo:N29 M204 S200*95
11:14:09.442 : N32 G1 X54.587 Y-17.336 E2.73587*121
11:14:09.442 : Setting Print and Travel Acceleration: 200.00
11:14:09.442 : ok
11:14:09.442 : echo:N30 G1 X54.352 Y-18.061 E2.56986 F3000*20
11:14:09.505 : ok
11:14:09.505 : echo:N31 M117 ETE -55s*28
11:14:09.505 : ok
11:14:09.505 : N33 G1 X55.942 Y-12.28 E3.87567*65
11:14:09.505 : echo:N32 G1 X54.587 Y-17.336 E2.73587*121
11:14:09.505 : N34 G1 X56.101 Y-11.535 E4.04164*123
11:14:09.536 : ok
11:14:09.536 : N35 M117 ETE -55s*24
11:14:09.536 : echo:N33 G1 X55.942 Y-12.28 E3.87567*65
11:14:11.538 : echo:busy: processing
11:14:13.554 : echo:busy: processing
11:14:15.570 : echo:busy: processing
11:14:17.587 : echo:busy: processing
11:14:19.604 : echo:busy: processing
11:14:21.620 : echo:busy: processing
11:14:23.698 : echo:busy: processing
11:14:25.704 : echo:busy: processing
11:14:27.720 : echo:busy: processing
11:14:29.731 : echo:busy: processing
11:14:31.747 : echo:busy: processing
11:14:33.794 : echo:busy: processing
11:14:35.804 : echo:busy: processing
11:14:36.148 : ok
11:14:36.148 : N36 M117 ETE -55s*27
11:14:36.148 : N37 G1 X56.919 Y-6.366 E5.18141*68
11:14:36.163 : echo:N34 G1 X56.101 Y-11.535 E4.04164*123
11:14:36.991 : ok
11:14:36.991 : echo:N35 M117 ETE -55s*24
11:14:36.991 : N38 M117 ETE -55s*21
11:14:36.991 : ok
Is that busy processing normal? I can feel that in these moments the extruder motor in vibrating (trying to move) but doesn't do it at all.
Also I give the echo I get when I cancel the print:
11:14:39.132 : echo:Steps per unit:
11:14:39.132 : echo: M92 X35.56 Y35.56 Z35.56 E164266.67
11:14:39.132 : echo:Maximum feedrates (units/s):
11:14:39.132 : echo: M203 X100.00 Y100.00 Z100.00 E25.00
11:14:39.132 : echo:Maximum Acceleration (units/s2):
11:14:39.132 : echo: M201 X9000 Y9000 Z9000 E10000
11:14:39.148 : echo:Acceleration (units/s2): P<print_accel> R<retract_accel> T<travel_accel>
11:14:39.148 : echo: M204 P3000.00 R3000.00 T3000.00
11:14:39.148 : echo:Advanced: S<min_feedrate> T<min_travel_feedrate> B<min_segment_time_ms> X<max_xy_jerk> Z<max_z_jerk> E<max_e_jerk>
11:14:39.148 : echo: M205 S0.00 T0.00 B20000 X20.00 Y20.00 Z20.00 E5.00
11:14:39.148 : echo:Endstop adjustment:
11:14:39.148 : echo: M666 X0.00 Y0.00 Z0.00
11:14:39.164 : echo:Delta settings: L<diagonal_rod> R<radius> H<height> S<segments_per_s> B<calibration radius> XYZ<tower angle corrections>
11:14:39.164 : echo: M665 L568.00 R361.00 H250.00 S200.00 B159.00 X0.00 Y0.00 Z0.00
11:14:39.164 : echo:PID settings:
11:14:39.164 : echo: M301 P22.20 I1.08 D114.00
11:14:39.304 : N1 M110*34
11:14:39.304 : N2 M115*36
11:14:39.304 : N3 M105*36
11:14:39.304 : N4 M114*35
11:14:39.351 : N5 M111 S7*99
11:14:39.351 : N6 T0*60
11:14:39.351 : N7 M80*28
11:14:39.430 : ok
Hope you have more info now.