Almost there?

hpgl/circles.hpgl

 SP1;
-PA12279,11040;
-PR2100,-2180;
-CI1486;
-PR0,-1486;
-CI1486;
-PR0,-1486;
-CI1486;
-PA;
-SP0;
+PA2,1.5;
+CI1.5;
+PA2,3;
+CI1.5;
+PA2,6;
+CI1.5;
+SP0;
\ No newline at end of file

hpgl/dot.hpgl

-PA3879,0;PR1050,1066;PD;PU;SP0;PA;
+SP1;
+PA1,2;PD;PU;
+SP0;
\ No newline at end of file

hpgl/et0.hpgl

+IN;SP1;PU0,0;PU11037,7495;PD11036,7427,11054,7380,11073,7365,11101,7359,11369,7383,11736,7437,12073,7498,12249,7543,12295,7576,12326,7616,12353,7711,12330,10067,12316,10153,12275,10239,12195,10311,12136,10337,12062,10354,11878,10360,11687,10341,11475,10304;PU12249,8579;PD11811,8578,11166,8567,10265,8520;PU10964,8158;PD8543,7989;PU9922,8326;PD9942,8635,9965,9150,9957,9687,9940,10055,9922,10248;PU0,0;PU0,0;SP0;IN;

hpgl/et1.hpgl

+IN;SP1;PU0,0;PU10845,8371;PD10765,8319,10583,8188,10392,8013,10321,7921,10281,7831,10287,7757,10337,7701,10423,7666,10537,7656,10695,7686,10872,7758,11060,7867,11251,8004,11629,8305;PU11766,8486;PD11866,9503,11875,9782,11861,9909,11834,10024,11791,10123,11731,10201,11652,10256,11554,10283,11436,10285,11328,10265,11231,10231,11148,10188,11028,10103,10985,10064;PU11685,8986;PD11501,8929,11069,8810,10816,8753,10569,8710,10350,8690,10181,8705,10124,8739,10087,8803,10066,8893,10059,9004,10075,9272,10109,9572,10139,9869,10139,10127,10121,10230,10086,10310,10033,10363,9957,10383,9875,10376,9821,10355,9781,10323;PU10655,8555;PD8877,8443;PU0,0;PU0,0;SP0;IN;

hpgl/et2.hpgl

+IN;SP1;PU0,0;PU11607,8787;PD11666,9091,11708,9367,11731,9636,11721,9889,11698,10016,11662,10135,11609,10240,11536,10322,11443,10377,11326,10397,11205,10381,11097,10336,11002,10272,10922,10198,10810,10061,10771,9998;PU11507,8550;PD11277,8315,11070,8117,10870,7951,10573,7746,10423,7669,10353,7647,10290,7639,10249,7648,10218,7671,10198,7710,10194,7761,10208,7826,10245,7903,10306,7990,10396,8089,10671,8337,11022,8634,11331,8894,11482,9031,11515,9082,11533,9133,11529,9154,11514,9169,11438,9174,11049,9135,10590,9112,10539,9119,10495,9138,10429,9210,10389,9323,10374,9471,10393,9937,10421,10297,10423,10353,10413,10402,10382,10434,10321,10441,10109,10410;PU10671,8918;PD9192,8475;PU0,0;PU0,0;SP0;IN;

hpgl/et3.hpgl

+IN;SP1;PU0,0;PU11309,9051;PD11429,9215,11528,9372,11609,9538,11677,9780,11693,9909,11693,10034,11673,10151,11628,10252,11555,10331,11450,10382,11328,10398,11208,10379,11090,10330,10978,10258,10872,10167,10774,10064,10611,9843;PU11178,8808;PD11107,8543,11024,8294,10915,8036,10806,7845,10673,7668,10600,7594,10525,7537,10449,7499,10374,7485,10295,7499,10232,7540,10186,7603,10158,7683,10148,7777,10157,7879,10186,7985,10236,8090,10314,8205,10409,8322,10627,8547,10834,8732,10973,8845,11105,8956,11134,9009,11123,9066,11093,9105,11054,9133,10943,9183,10786,9259,10577,9404,10480,9511,10421,9635,10386,9770,10367,9908,10328,10171,10287,10283,10218,10374,10166,10403,10103,10421,9962,10436,9793,10430;PU10355,9369;PD9069,8714;PU0,0;PU0,0;SP0;IN;

hpgl/et4.hpgl

+IN;SP1;PU0,0;PU9723,8757;PD9976,9208,10192,9572,10378,9852,10558,10064,10652,10155,10751,10233,10857,10296,10971,10343,11094,10371,11229,10379,11324,10364,11415,10323,11498,10259,11568,10175,11624,10073,11661,9958,11676,9830,11665,9693,11637,9589,11590,9480,11451,9259,11270,9054,11070,8892,10898,8786,10699,8656,10508,8489,10426,8388,10358,8274,10312,8116,10308,8028,10319,7942,10348,7861,10396,7790,10467,7736,10562,7702,10653,7698,10751,7718,10848,7763,10939,7834,11018,7931,11079,8054,11115,8203,11119,8380,11098,8524,11056,8680,10928,8999,10777,9284,10644,9477,10526,9603,10403,9711,10168,9877,9991,9976,9921,10009;PU0,0;PU0,0;SP0;IN;

hpgl/grid-lines.hpgl

 LT;
 SP1;
-PA729,0;PR;
-PD0,5520;PU1050,0;
-PD0,-5520;PU1050,0;
-PD0,5520;PU1050,0;
-PD0,-5520;PU0,323;
-PD-3879,0;
-PU0,743;PD3879,0;
-PU0,743;PD-3879,0;
-PU0,743;PD3879,0;
-PU0,743;PD-3879,0;
-PU0,743;PD3879,0;
-PU0,743;PD-3879,0;
-PU0,743;PD3879,0;
+PA0,0;
+PD0,8;PU1,8;
+PD1,0;PU2,0;
+PD2,8;PU3,8;
+PD3,0;PU4,0;
+PD4,8;
+PD0,8;
+PU0,7;PD4,7;
+PU4,6;PD0,6;
+PU0,5;PD4,5;
+PU4,4;PD0,4;
+PU0,3;PD4,3;
+PU4,2;PD0,2;
+PU0,1;PD4,1;
+PU4,0;PD0,0;
 PU;
-PA;
 SP0;
 

hpgl/he-curved.hpgl

+SC1000,2000,-700,1500;SP1;PA1136,716;PD;PA1160,724,1184,733,1208,741,1232,748,1257,754,1269,757,1281,760,1293,762,1305,764,1316,766,1328,767,1340,768,1351,768,1363,768,1374,768,1385,767,1396,765,1407,763,1418,761,1428,757,1438,753,1448,749,1458,744,1467,738,1477,731,1486,724,1494,716,1503,707,1511,698,1518,689,1525,680,1537,661,1548,642,1557,622,1564,602,1569,581,1573,561,1576,539,1577,518,1577,496,1576,473,1574,451,1572,428,1568,405,1564,382,1560,359,1555,335,1544,288,1532,240,1521,192,1510,143,1506,119,1502,95,1499,71,1496,47,1495,24,1494,0;PU;PA1136,0;PD;PA1136,358;PU;PA1494,0;PA1494,716;PA1136,716;PA1136,0;PA1136,358;PA0,0;SP0
\ No newline at end of file

hpgl/he-straight.hpgl

+SC1000,2000,-700,1500;SP1;PA1136,716;PD;PA1494,716,1494,0;PU;PA1136,0;PD;PA1136,358;PU;PA1494,0;PA1494,716;PA1136,716;PA1136,0;PA1136,358;PA0,0;SP0
\ No newline at end of file

hpgl/line-2.hpgl

-PA8079,0;
+PA1,1;

hpgl/line-3.hpgl

-PR1050,323;PD2100,2972;
+PD3,5;
\ No newline at end of file

hpgl/line-4.hpgl

-PU;
+PU;
\ No newline at end of file

hpgl/line-5.hpgl

-SP0;PA;
+SP0;
\ No newline at end of file

hpgl/line.hpgl

 SP1;
 PA8079,0;
-PR1050,323;PD2100,2972;PU;
-PA;SP0;
+PR1050,323;PD2100,2972;
+PU;
+SP0;PA;

hpgl/runner.sh

-files=(init-dance.hpgl grid-lines.hpgl dot.hpgl line-1.hpgl line-2.hpgl line-3.hpgl line-4.hpgl line-5.hpgl corner.hpgl circles.hpgl esperluette-rough.hpgl he-rough.hpgl);
+files=(init-dance.hpgl page-8.hpgl grid-lines.hpgl page-1.hpgl dot.hpgl page-2.hpgl line-1.hpgl line-2.hpgl line-3.hpgl line-4.hpgl line-5.hpgl page-3.hpgl corner-1.hpgl corner-2.hpgl corner-3.hpgl corner-4.hpgl corner-5.hpgl corner-6.hpgl page-4.hpgl circles.hpgl page-5.hpgl et-0.hpgl et-1.hpgl et-2.hpgl et-3.hpgl et-4.hpgl page-6.hpgl he-straigt.hpgl he-curved.hpgl page-7.hpgl);
 
 # Script to loop through the hpgl files and write them directly to the plotter
 
 for hpglfile in ${files[*]}
 do
 	#echo $hpglfile;
-	cat $hpglfile > /dev/ttyUSB0;
+	cat $hpglfile | tee -a plot.hpgl > /dev/ttyUSB0;
 	less $hpglfile;
 done